particle size of calf starter: effects on digestive …

The Pennsylvania State University

The Graduate School

College of Agricultural Sciences

PARTICLE SIZE OF CALF STARTER EFFECTS ON DIGESTIVE SYSTEM

DEVELOPMENT AND RUMEN FERMENTATION

A Dissertation in

Animal Science

by

Francisco Xavier Suarez-Mena

2014 Francisco Xavier Suarez-Mena

Submitted in Partial Fulfillment

of the Requirements

for the Degree of

Doctor of Philosophy

December 2014

The dissertation of Francisco Xavier Suarez-Mena was reviewed and approved by the following

Arlyn J Heinrichs

Professor of Dairy and Animal Science

Dissertation Advisor

Chair of Committee

Kevin D Harvatine

Assistant Professor of Nutritional Physiology

Chad Dechow

Associate Professor of Dairy Cattle Genetics

Robert J Van Saun

Professor of Veterinary Science

Terry D Etherton

Distinguished Professor of Animal Nutrition

Head of the Department of Animal Science

Signatures are on file in the Graduate School

iii

ABSTRACT

Starter intake before weaning is the conditional factor to rumen development and thus to

a successful transition at weaning Rumen development can be negatively affected when the

particle size of starter is too small resulting in abnormal papillae and hyper-keratinization of the

rumen epithelium Two common strategies to increase particle size of starter are to add forage to

the diet or to reduce the processing of grain The two strategies were tested and the literature

was reviewed in regards to the effects of forage on starter intake

The effects of forage on starter intake in pre-weaned dairy calves were reviewed as

research studies have yielded inconsistent results Discrepancies in the literature come from

differences in starter ingredient composition forage source particle size of starter and forage and

intake level All of these factors will affect calvesrsquo intake response to forage in their diet Some

important factors that will affect intake such as starch content and particle size of starter were

often not reported which limited the analysis of this review It was also noted that segregating

intake by wk particularly for pre-weaned vs post-weaned periods when reporting intake data

would help to determine the level of forage intake that impacts starter intake

Effects of grain processing in calf starter were evaluated in young calves A series of 3

trials were conducted to determine effects of whole or ground oats in starter grain on

reticulorumen fermentation and digestive system development of pre-weaned calves Male

Holstein calves (431 plusmn 23 kg at birth n = 8 9 and 7 for trials 1 2 and 3 respectively) were

housed in individual pens in a heated facility bedding was covered with landscape fabric to avoid

any consumption of bedding In trials 1 and 2 only calves were fitted with a rumen cannula by

wk 2 of life In all trials a fixed amount of starter (containing 25 oats either ground and pelleted

or whole) was offered daily orts were fed through the cannula in trials 1 and 2 Calves were

randomly assigned to all pelleted starter or pellets plus whole oats Weekly measurements of

iv

rumen digesta pH did not change and only subtle changes were observed in molar proportions of

individual volatile fatty acids Molar proportion of butyrate and pH linearly decreased with age

while acetate proportion increased Reticulorumen weight and papillae length tended to be greater

for calves fed pelleted starter while abomasum weight was greater for calves fed pellets plus

whole oats Fecal particle size and starch content were greater for calves fed pellets plus whole

oats Under the conditions of this study physical form of oats in starter grain did not affect rumen

fermentation parameters greater rumen weight and papillae length in calves fed pelleted starter

may be a result of greater nutrient availability of ground oats Under the conditions of this study

with young calves on treatments for lt 4 wk increasing particle size of starter by feeding whole

oats did not affect rumen fermentation nor did appear to improve digestive system development

Additionally the effects of increasing particle size of calf starter by changing the particle

length of straw were evaluated in young calves Two trials were conducted to determine effects of

straw particle size in calf starter on rumen fermentation and development Holstein calves (n =

45) were housed in individual pens bedding (wood shavings) was covered with landscape fabric

to completely avoid consumption of bedding Milk replacer was fed at 12 of birth body

weightd and water offered free choice Calves were randomly assigned to 4 treatments differing

in geometric mean particle length (Xgm) of straw comprising 5 of starter dry matter Straw was

provided within the pellet at manufacturing (PS 082 mm Xgm) or mixed with the pellet at time

of feeding at Xgm of 304 (SS) 710 (MS) or 127 (LS) mm Calves (n = 12 3treatment) in trial

1 were fitted with a rumen cannula by wk 2 of age A fixed amount of starter that was adjusted

with age was offered orts were fed through the cannula in cannulated calves Calves were

euthanized 6 wk after starter was offered (9 and 7 wk of age for trials 1 and 2) Rumen digesta pH

linearly decreased with age while volatile fatty acid concentration increased with age Overall pH

had a cubic trend with SS lower than that of PS and MS likely related to intake changes and not

to treatments Molar proportion of acetate decreased with age while propionate proportion

v

increased Overall molar proportions of volatile fatty acids were not affected by diet Fecal Xgm

was not different in spite of changes in diet particle size and rumen digesta of PS being greater

than SS MS and LS at slaughter Fecal pH and starch concentration were not affected by diet

however pH decreased while starch content increased with age Weight of stomach

compartments rumen papillae length and width and rumen wall thickness did not differ between

diets Omasum weight as a percentage of body weight at harvest linearly decreased as straw

particle size increased Under the conditions of this study modifying straw particle length in

starter grain resulted in minimal rumen fermentation parameter changes and no changes in rumen

development Rumen pH and fermentation changes with age were likely the result of increasing

starter intake

Particle size of calf starters can be modified by changing grain processing or by adding

forage Factors such as intake level and ingredient and chemical composition will influence the

effects of particle size on rumen fermentation and rumen development Calves can tolerate lower

rumen pH levels than adult cattle however high intake of starters with short particle size and

high starch concentration increase the risk of reaching pH levels that can negatively impact calf

health

vi

TABLE OF CONTENTS

List of Figures vii

List of Tables ix

Acknowledgements x

Chapter 1 Introduction 1

References 3

Chapter 2 Effect of forage on calf intake 5

Introduction 5

Description of analyzed studies 6

Analysis 8

Conclusions 12

References 14

Chapter 3 Whole oats in calf starters 17

Abstract 17

Introduction 18

Materials and methods 19

Sample analyses 22

Statistical analyses 23

Results and discussion 24

Rumen fermentation 25

Particle size starch content and pH of feces 31

Digestive organ measurements 33

Conclusions 35

References 37

Appendix 1 57

Chapter 4 Straw particle size in calf starters Effects on digestive system development

and rumen fermentation 59

Abstract 59

Introduction 60



Rumen fermentation and digesta particle size 68



Conclusions 73

References 75

Chapter 5 Summary and conclusions 92

vii

LIST OF FIGURES

Figure 3-1 Starter intake of calves fed ground (G) or whole (W) oats in the starter Data

comes from 3 trials with 8 9 and 7 calves for trials 1 2 and 3 respectively Calves

in trials 1 and 2 were fitted with rumen cannulas and calves in trial 1 were

slaughtered on d 22 Total starter intake (T) is the cumulative of voluntary intake (V)

plus starter introduced through rumen cannulae Diet effect for voluntary and

cumulative intakes (P gt 01) 50

Figure 3-2 Mean voluntary starter intake of calves fed ground or whole oats in starter

Data comes from 3 trials with 8 9 and 7 calves for trials 1 (solid line) 2 (- - -) and

3 () respectively Calves in trials 1 and 2 were fitted with rumen cannulae and

orts from their daily starter allotment were put through the cannula that starter is not

reflected in this figure Trial effect up to d 21 (P gt 010) trial effect d 22 to 28 (P lt

001) trial by diet interaction (P gt 010) 51

Figure 3-3 Mean rumen pH variation at -8 -4 0 2 4 8 and 12 h relative to feeding

from 1 to 4 wk after starter was available for calves fed ground or whole oats in the

starter (n = 17 up to wk 3 and 9 in wk 4) Linear effect for wk (P lt 001) cubic

effect for time relative to feeding (P lt 001) 52

Figure 3-4 Mean rumen VFA concentration at -8 -4 0 2 4 8 and 12 h relative to

feeding from 1 to 4 wk after starter was available for calves fed ground or whole

oats in the starter (n = 17 up to wk 3 and 9 in wk 4) Quadratic effect for wk (P lt

001) cubic effect for time relative to feeding (P lt 001) 53

Figure 3-5 Mean rumen acetate propionate and butyrate molar percentage of total VFA

at -8 -4 0 2 4 8 and 12 h relative to feeding for wk 1 to 4 after starter was

available for calves fed ground or whole oats in the starter (n = 17 up to wk 3 and 9

in wk 4) Acetate and butyrate cubic effect for time relative to feeding (P lt 005)

Propionate effect for time relative to feeding linear (P = 006) and cubic effect (P =

015) 54

Figure 3-6 Mean rumen NH3 concentration at -8 -4 0 2 4 8 and 12 h relative to


oats in the starter (n = 17 up to wk 3 and 9 in wk 4) Linear effect for wk (P lt 001)

cubic effect for time relative to feeding (P lt 001) 55

Figure 3-7 Mean fecal pH (solid lines) and starch (dashed lines) concentration from 1 to

4 wk after starter was available for calves fed ground (n = 11 up to wk 3 and 7 in wk

4) or whole oats (n = 13 up to wk 3 and 9 in wk 4) in the starter Diet effect for

pH (P gt 010) and starch concentration (P lt 001) Linear effect of wk (P lt 001) for

both variables Diet by wk interaction for starch (P lt 005) 56

Figure 3-8 Example of rumen papillae slides at 20times magnification scored as normal (A)

and abnormal (B) papillae 57



viii

Figure 4-1 Mean solid feed intake (17 calves ) and rumen pH (12 calves diams) from 1 to

6 wk after starter was available for calves fed starter containing 5 straw differing

in particle size either in the pellet (PS) or mixed with the pellet Short (SS) Medium

(MS) and Long (LS) in Trial 1 87


from 1 to 6 wk after starter was available for 12 calves fed starter containing 5

straw differing in particle size either in the pellet (PS) or mixed with the pellet Short

(SS) Medium (MS) and Long (LS) in Trial 1 Linear effect for wk (P lt 001) cubic


Figure 4-3 Mean rumen pH variation at -8 -4 0 2 4 8 and 12 h relative to feeding 5

wk after solid feed was available for 12 calves that showed (5 calves ) or did not

show (7 calves ) acidosis symptoms in Trial 1 The probability for the 3-way

interaction for acidosis symptoms vs not week and time from feeding was (P lt

001) Differences between groups at 8 and 12 h after feeding were significant (P lt

005) 89

Figure 4-4 Mean total VFA variation at -8 -4 0 2 4 8 and 12 h relative to feeding





Figure 4-5 Mean fecal pH () and starch () concentration from 1 to 6 wk after starter

was available for calves fed starter containing 5 straw differing in particle size

either in the pellet (PS) or mixed with the pellet Short (SS) Medium (MS) and

Long (LS) Linear effect of wk (P lt 001) for both variables 91

Figure 5-1 Mean as-fed starter intake (full line) from 1 to 6 wk after starter was

available for calves in Chapter 3 () and Chapter 4 (Trial 1) Mean rumen pH

concentration (dashed line) for cannulated calves in Chapter 3 () and Chapter 4

() 95

ix

LIST OF TABLES

Table 3-1 Ingredient and chemical composition and particle size of starters containing

ground oats in a pelleted feed (G) or whole oats plus a pellet (W) 42

Table 3-2 Description of calves fed starters containing ground oats in a pelleted feed (G)

or whole oats plus a pellet (W) 44

Table 3-3 Rumen fermentation of calves fed starters containing ground oats in a pelleted

feed (G) or whole oats plus a pellet (W) 45

Table 3-4 Rumen contents particle size of calves fed starters containing ground oats in a

pelleted feed (G) or whole oats plus a pellet (W) 46

Table 3-5 Fecal particle size and xylose absorption of calves fed starters containing


Table 3-6 Digestive system development measurements in calves fed starters containing



5 straw differing in particle size either in the pellet (PS) or mixed with the pellet

Short (SS) Medium (MS) and Long (LS) 78

Table 4-2 Description of calves fed starters containing 5 straw differing in particle size


Long (LS) 80

Table 4-3 Intake of calves fed starters containing 5 straw differing in particle size


Long (LS) 81

Table 4-4 Rumen fermentation of 12 calves fed starters containing 5 straw differing in

particle size either in the pellet (PS) or mixed with the pellet Short (SS) Medium


Table 4-5 Rumen contents particle size of calves fed starters containing 5 straw

differing in particle size either in the pellet (PS) or mixed with the pellet Short (SS)

Medium (MS) and Long (LS) 84

Table 4-6 Starch concentration pH and fecal particle size of calves fed starters

containing 5 differing in particle size either in the pellet (PS) or mixed with the

pellet Short (SS) Medium (MS) and Long (LS) in Trial 1 85

x

ACKNOWLEDGEMENTS

First I want to thank my family for their support and motivation which has been

fundamental in all this years away from home

I am grateful for the opportunity to work learn and be associated with the Department of

Animal Science and The Pennsylvania State University I would especially like to thank Dr

Heinrichs for his friendship his mentorship and the opportunities he has made available for me

His advice guidance help and encouragement throughout my graduate studies have been

invaluable

I would also like to express my sincere appreciation to Dr Harvatine Dr Dechow and

Dr Van Saun for their service as committee members They provided me with guidance and

advice and were always available to lend me a hand with my research

I am grateful to all the people that have been members of Dr Heinrichs lab in the time

Irsquove been here graduate and undergraduate students technicians and interns Without their help I

wouldnrsquot have been able to accomplish this work I must thank Coleen Jones and Maria Long for

their help in their own specialties and also for their friendship The collaboration from Dr

Harvatinersquos and Dr Hristovrsquos lab grouprsquos members is much appreciated especially Jackiersquos

enthusiasm and willingness to help

Finally I thank my friends from across the department and the University some for their

help with my research and class work and all for the good times in this great town

1

Chapter 1

Introduction

At birth the calfrsquos digestive system capabilities are similar to a monogastric animal as the

fore stomach compartments (rumen reticulum and omasum) which are essential for solid feed

digestion have not yet developed (Warner 1991 Baldwin et al 2004) Until the fore stomach

compartments develop the calf needs to obtain its nutrition from milk which is the main product

to generate income on most dairy farms Early weaning is a common practice to reduce the

amount of milk fed and with it the cost of feeding calves (Klein et al 1987) To successfully

wean calves early the fore stomach compartments need to be developed so the calf can get its

nutrient requirements from solid feed (Stobo et al 1966 Klein et al 1987)

The rumen needs to grow in size but more important is the development of rumen

papillae because papillae increase the absorptive surface area of the reticulo-rumen (Barcroft et

al 1944) The rumen epithelium is involved in the absorption transport and metabolism of

volatile fatty acids (VFA) and along with its development the calf will transition from a

glycolytic to a gluconeogenic liver metabolism The latter was reviewed by Baldwin et al (2004)

and is outside of the scope of this dissertation However it should be pointed out that Baldwin et

al (2004) concluded that the mechanisms regulating rumen development such as ontogenic

control and nutrient and endocrine factors are not yet completely understood

Research from Cornell University lead by Warner (Warner 1956 Warner et al 1956)

suggested that rumen epithelium development is stimulated by chemical properties of feeds rather

than by their physical nature Brownlee (1956) an European researcher reached the same

conclusions in independent research published the same month suggesting that papillae

2

development is dependent on the nature of food and not predetermined and that the energy

content and rumen fermentability of feeds determine papillae development These findings were

confirmed in a study using solutions of VFA salts and sponges and it was observed that papillae

grew in calves receiving the VFA salts but did not grow in calves receiving plastic sponges alone

Hence the products of rumen fermentation are responsible for the development of rumen

papillae not the coarseness of feeds (Flatt et al 1958) It was further determined that butyrate

and propionate are the most important VFA for papillae growth (Sander et al 1959 Tamate et

al 1962) Concentrates in the diet increase the production of propionate and butyrate (Carroll

and Hungate 1954) thus as the proportion of concentrates increases the development of papillae

is enhanced (Stobo et al 1966) Fermentation of forage results in a greater proportion of acetate

and proceeds at a slower rate than that of concentrates (Davis and Drackley 1998) Furthermore

fiber-digesting microorganisms take longer than starch- and sugar-digesting microorganisms to

become established in the rumen (Anderson et al 1987) and the ingestion of hay limits energy

intake (Stobo et al 1966) Hence the current recommendations for pre-weaned calves discourage

feeding long hay to calves until after weaning However the particle size of feed is recognized as

important in preventing abnormal development of rumen papillae (Davis and Drackley 1998

NRC 2001)

The effects of feeding forage on calf starter intake were reviewed because the literature

reports conflicting findings (Chapter 2) Increasing the particle size of the solid portion of calvesrsquo

diets can be done by either adding forage to the diet or by reducing the processing of grain I

tested both strategies by changing grain processing in one study (Chapter 3) and by changing the

particle size of a small amount of forage in another study (Chapter 4)

3

References

Anderson K L T G Nagaraja J L Morrill T B Avery S J Galitzer and J E Boyer 1987

Ruminal microbial development in conventionally or early-weaned calves J Anim Sci

641215ndash1226

Baldwin R L K R McLeod J L Klotz and R N Heitmann 2004 Rumen development

intestinal growth and hepatic metabolism in the pre- and postweaning ruminant J Dairy

Sci 87E55ndashE65

Barcroft J R A McAnally and A T Phillipson 1944 The absorption of sodium ortho-iodo-

hippurate from the rumen of lambs J Exp Biol 20132ndash134

Brownlee A 1956The development of rumen papillae in cattle fed on different diets Brit Vet

J 112369-375

Carroll E J and R E Hungate 1954 The magnitude of the microbial fermentation in the

bovine rumen Appl Microbiol 2205ndash214

Davis C L and J K Drackley 1998 The Development Nutrition and Management of the

Young Calf Iowa State Univ Press Ames IA

Flatt W P R G Warner and J K Loosli 1958 Influence of purified materials on the

development of the ruminant stomach J Dairy Sci 411593ndash1600

Klein R D R L Kincaid A S Hodgson J H Harrison J K Hillers and J D Cronrath 1987

Dietary fiber and early weaning on growth and rumen development of calves J Dairy

Sci 702095ndash2104

NRC 2001 Nutrient Requirements of Dairy Cattle 7th rev ed Natl Acad Press Washington

DC

Sander E G R G Warner H N Harrison and J K Loosli 1959 The stimulatory effect of

sodium butyrate and sodium propionate on the development of rumen mucosa in the

young calf J Dairy Sci 421600ndash1605

Stobo I J F J H B Roy and H J Gaston 1966 Rumen development in the calf 1 The effect

of diets containing different proportions of concentrate to hay on rumen development Br

J Nutr 20171ndash188

Tamate H A D McGilliard N L Jacobson and R Getty 1962 Effect of various dietaries on

the anatomical development of the stomach in the calf J Dairy Sci 45408ndash420

Warner R G 1956 The relative influence of milk hay and grain on the development of the

ruminant stomach Pages 128ndash133 in Proc Cornell Nutr Conf Feed Manuf Cornell

Univ Ithaca NY

4

Warner R G 1991 Nutritional factors affecting the development of a functional ruminant A

historical perspective Pages 1ndash12 in Proc Cornell Nutr Conf Feed Manuf Cornell

Univ Ithaca NY

Warner R G W P Flatt and J K Loosli 1956 Dietary factors influencing the development of

the animals stomach J Agric Food Chem 4788ndash792

5

Chapter 2

Effect of forage on calf intake

Introduction

Until the 1950s it was generally believed that forages were necessary for rumen

development and papillae growth (Hibbs et al 1953 Davis and Drackley 1998) However

research from Cornell University lead by Warner (Warner 1956 Warner et al 1956 Flatt et al

1958) and in Europe by Brownlee (1956) changed that belief by showing that rumen epithelium

development is stimulated by the end products of feed fermentation rather than by the physical

nature of feeds It was further determined that butyrate and propionate are the most important

volatile fatty acids (VFA) for rumen papillae growth (Sander et al 1959 Tamate et al 1962)

Concentrates in the diet were found to increase the production of propionate and butyrate (Carroll


is enhanced (Stobo et al 1966) Fermentation of forage proceeds at a slower rate than

concentrate and results in a greater proportion of acetate (Davis and Drackley 1998)

Furthermore fiber digesting microorganism take longer than starch and sugar digesting

microorganism to get established in the rumen (Anderson et al 1987) and the ingestion of hay

limits energy intake due to feed density (Stobo et al 1966) Hence the current recommendations

for pre-weaned calves discourage feeding long hay to calves until after weaning (Davis and

Drackley 1998 NRC 2001)

Studies investigating the effects of forage in calf diets have yielded inconsistent results

(Coverdale et al 2004) Forage addition to calf diets has been reported to reduce starter intake in

several studies (Hibbs et al 1956 Stobo et al 1966 Hill et al 2008) while others have

concluded that it increases starter intake (Kincaid 1980 Thomas and Hinks 1982 Coverdale et

6

al 2004 Khan et al 2011 Castells et al 2012) Starter intake before weaning is an important

factor to rumen development and thus to a successful transition at weaning Hence it is important

to understand the factors that make calves change their eating behavior by the addition of forage

to their diet Therefore the scope of this review is to evaluate the literature in regard to effects of

forage inclusion in the diet on starter intake of dairy calves

Description of analyzed studies

In spite of research showing that concentrates are more effective than forage in inducing

rumen development the addition of forage to the calf diet is still being studied Early studies

investigated the addition of concentrates to forage in young calf diets Hibbs et al (1956) fed 41

32 and 23 grass hay to grain ratio to calves from 4 d to 12 wk of age and weaned at 7 wk Grain

intake increased as the proportion of concentrates increased Similar results were obtained by

Stobo et al (1966) in calves fed ad libitum hay and a fixed concentrate allowance at 045 091

136 181 or 227 kgd from 3 to 12 wk of age and weaned at 5 wk As concentrate allowance

increased calves ate more concentrate and less forage The intake response to forage

concentration was tested on older calves by Jahn et al (1970) 5 levels of straw (5 to 60 straw)

were tested in calves weaned from 8 to 20 wk of age Intake increased until 325 straw level and

decreased thereafter Weaning was much later in this study but overall the results had many

similarities to other studies

Later the emphasis was not only on forage concentration but also on the physical form of

forage being fed Kincaid (1980) studied the addition of alfalfa to starter by feeding 4 diets either

all concentrate concentrate mixed with 20 alfalfa pellets and concentrate with either free

choice alfalfa pellets or long-stem alfalfa Diets were fed from 0 to 12 wk of age and calves were

weaned at 4 wk Total intake was higher for calves fed alfalfa hay over the 12-wk period

7

followed by alfalfa pellets both ad libitum and mixed with concentrates and lowest for all

concentrate Concentrate intake was not different between treatments The effects of

incorporating forage with different physical form to calf diets were also investigated by Thomas

and Hinks (1982) Up to 3 wk of age no effect on intake was detected but between 3 and 5 wk

the addition of 18 chopped straw within the pellet resulted in greater concentrate intake than an

all concentrate diet while ad libitum chopped or long straw had no effect Between 5 and 9 wk of

age (weaning occurred at 5 wk) the concentrate intake of the 18 chopped straw diet was greater

than the all concentrate and ad libitum chopped straw diets while the ad libitum long straw diet

was not different from any of the other diets Cummins et al (1982) also investigated the effects

of physical form of forage but in older calves (8 to 12 wk) 2 diets containing about 40 grass

hay either ground or chopped and an all concentrate diet were tested Calves on the ground hay

diet had the highest DMI followed by concentrates only and DMI was lowest for chopped hay It

is apparent from these studies that long hay does not have a beneficial impact on intake later

studies have investigated the addition of chopped forage and generally at lower inclusion rates

More recent studies have looked at lower rates of forage inclusion Coverdale et al

(2004) observed that the inclusion of chopped grass hay at 75 and 15 of dry feed did not

change intake behavior prior to weaning (about 30 d) After weaning starter consumption was

greater for the diets supplemented with forage In a series of studies Hill et al (2008) observed

that texturized starters containing 5 cottonseed hulls or 5 chopped hay did not affect intake up

to 8 wk of age in calves weaned at 4 wk However from 8 to 12 wk calves on the cottonseed

starter had greater intake Similarly the inclusion of 0 5 or 10 chopped hay in texturized

starters yielded similar intakes up to 8 wk of age but when the inclusion of 5 was compared to

15 from 8 to 12 wk intake was greater for the lower hay inclusion diet

Recently there has been significant interest in feeding higher amounts of milk to calves in

accelerated growth programs and the effects of forage in such rearing programs were explored by

8

Khan et al (2011) Calves were fed higher volumes of milk (about 20 of BW at birth) and

gradually weaned by 8 wk of age Starter was fed by itself or it was supplemented with ad libitum

access to chopped grass hay Similar intakes were observed until 5 wk but from 6 to 10 wk

starter intake tended to be greater for calves fed starter only nevertheless total solid DMI in this

period was greater for calves receiving hay

In a recent article Castells et al (2012) evaluated the inclusion of ad libitum forage to

calf diets in 3 studies Starter was fed along with or accompanied by 1 of several forage options

corn silage triticale silage alfalfa grass or oats chopped hay and chopped barley straw Solid

feed was fed from 2 to 10 wk of age and calves were weaned at 8 wk Starter intake of calves

receiving starter only was lower than oats hay barley straw and triticale silage but not different

from the other forage diets Differences in starter intake between starter only and triticale silage

oats hay and barley straw started as early as 4 5 and 6 wk of age respectively Two more studies

from the same group were published the following year Terreacute et al (2013) looked into the

addition of chopped oat hay fed ad libitum and separately from 2 starters containing either high or

low NDF No effect on intake was detected in this study up to weaning at 5 wk but from 5 to 9

wk forage supplementation increased total DMI of the calves In the second study Castells et al

(2013) did not detect differences in starter or total DMI preweaning (1 to 8 wk of age) or post

weaning 8 to 10 wk of age when calves were fed starter only or supplemented with either alfalfa

or oats hay numerically calves eating oat hay had greater intake In these studies it was

concluded that forage availability is of benefit to increase starter intake

Analysis

In several of the studies where intake data was segregated by time intake behavior

changed with age (Thomas and Hinks 1982 Coverdale et al 2004 Hill et al 2008 Khan et al

9

2011 Castells et al 2012 Terreacute et al 2013) Therefore the effect of forage on starter intake

seems to be relative to starter consumption level As calves grew older and starter intake

increased it was more likely that forage supplementation changed overall intake behavior

Rumen development and with it the metabolism of the calf changes with the length of time that

calves have been eating starter This likely plays a role in the intake response to the addition of

forage or fiber to the diet However the amount of starter consumption is likely what has the

largest impact on calf feeding behavior because starters are high in rapidly fermentable

carbohydrates and this rapid fermentation can overwhelm the calvesrsquo capacity to maintain rumen

pH In adult cattle excessive intake of highly fermentable carbohydrates leads to rumen acidosis

(Krause and Oetzel 2006) which can change eating behavior When lactating cows were given

the choice between 2 diets after they were induced to acidosis they chose the diet with slower

starch fermentability and higher particle size (Maulfair et al 2013) Moreover as DMI increases

in adult cattle so does their requirement for physical structure in the diet (De Brabander et al

1999) Laarman et al (2012) observed that hay intake in calves was positively correlated to

rumen pH possibly because particle size of the consumed diet increased as more hay was

consumed Longer particle size increases the time calves spend ruminating (Hodgson 1971)

thereby affecting saliva production and rumen buffering (Krause and Oetzel 2006) So it could be

speculated that as the calf ages and its DM intake increases the need for forage to maintain

rumen pH is increased and the influence of forage on intake becomes more important and

possibly preferred by the calf

When intake analysis is not segregated over time and calves are kept on treatments for

several weeks the time at which forage influences intake cannot be accurately determined unless

all data has been reported by wk Consequently intake behavior findings in the Kincaid (1980)

study may have yielded different conclusions if pre- and post-weaning intakes were segregated

Also starters in the Kincaid (1980) study were possibly protein deficient (NRC 2001) so the N in

10

alfalfa could have also influenced intake behavior The earliest age at which forage availability

affected intake was reported in the Thomas and Hinks (1982) study where between 3 and 5 wk of

age calves fed concentrate only ate about 071 kgd of starter while calves fed the 18 straw in

the pellet diet ate 121 kgd This observation may be related to grain processing The corn in

Thomas and Hinks (1982) comprised 40 of starter and was flaked Lesmeister and Heinrichs

(2004) studied effects of corn processing in calf starters (33 of starter DM) and observed lower

starter intake and rumen pH with steam flaked corn in calves at 4 and 6 wk of age compared to

calves fed whole corn The process of steam flaking corn gelatinizes starch which increases its

solubility and digestibility in the rumen (Zinn et al 2002) Indeed the digestibility of starch in

steam flaked corn was found to be greater than whole ground or dry-rolled corn in feedlot cattle

(Corona et al 2005) Corn starch solubility in the Thomas and Hinks (1982) study may have

been further enhanced by pelleting which increases the surface area by reducing particle size In

older cattle when the rate and extent of starch digestibility is excessive it decreases DMI (Zinn et

al 2002) In the study by Thomas and Hinks (1982) the rumen pH of calves fed concentrates

only was lower than in calves fed 18 straw in the pellet This could be related to excessive

starch degradation after a meal which could contribute to depressed starter intake The nutrient

density dilution caused by adding straw to the pellet may have diminished the starch effect (by

decreasing the amount of acid produced) and enhanced intake In the Castells et al (2012) study

starter consumption also began to be affected early about 3 wk after solid feed was available

when starter intake was about 070 kgd Although starter particle size or form details were not

provided it is likely that the starter was in a pellet form as in the other studies from this group

(Castells et al 2013 Terreacute et al 2013) Under this assumption it is possible that the small

particle size of the starter also made starch digestibility overwhelm the buffering capacity so the

need for a forage source was observed at that intake level Also in the Castells et al (2012) trial

unusually high starter intakes were reported about 040 055 and 070 kgd for 1 2 and 3 wk

11

after solid feed was offered Starter intake (kgd) of calves in other studies from the same group

was about 053 from 1 to 7 wk of age (Terreacute et al 2013) and 061 from 1 to 8 wk (Castells et al

2013) In other studies with comparable calf management where daily starter intakes were

reported it took calves over 3 wk to reach 04 kgd of starter consumption (Lesmeister 2003

Bach et al 2007) So the early need for a forage source detected in the study (Castells et al

2012) was most likely due to a combination of high starter intake and rapidly fermentable starch

The previously mentioned starch concept also may explain conflicting intake behavior

observations between Hill et al (2008) and Jahn et al (1970) Diets in the second study contained

starch and sugar (glucose monohydrate) ingredients that are fermented very rapidly in the rumen

and at high levels can quickly depress pH thus calves needed higher straw consumption to

increase rumen buffering Calves in the Hill et al (2008) study that ate more when straw

inclusion was 5 vs 15 from 8 to 12 wk were fed a texturized starter which decreases

fermentability rate of starch because particle size of grain is greater About 80 of particles in

these starters were gt 118 mm in length

Ruminants calves will need forage in their diet however the time and amount of forage

needed will be dependent on several factors Davis and Drackley (1998) pointed out that the

amount of fiber in starter depends on the ingredient composition of the starter the particle size of

fiber and intake level It should be noted than in the studies presented here calves had access to

fibrous bedding materials such as straw and wood shavings which could alter or mitigate

treatment differences Phillips (2004) observed that grass fed calves spent less time per day lying

and eating straw bedding than calves fed starter only When the particle size of starter was

evaluated in calves fed no forage and without access to consume bedding materials up to 8 wk it

was determined that over 50 of particles should be larger than 119 mm to insure adequate

intake proper rumen fermentation (Warner et al 1973) and prevent physiological abnormalities

(Porter et al 2007) Young calves have very little voluntary intake of high fiber low energy

12

forages when offered ad libitum access to straw consumption was about 4 of solid feed intake

(Thomas and Hinks 1982 Castells et al 2013) Thus when bedded with straw they may be able

to get their fiber requirement from it Moreover voluntary intake of low quality forage may

decrease as calves age Fokkink et al (2011) observed straw intake to decrease from about 4 of

solid feed intake up to 5 wk of age (weaning time) to about 1 from 5 to 8 wk in calves that had

no access to consume bedding Particle size and processing of grain is important because it

modifies starch fermentability but the overall particle size of the starter is also important to

induce rumination and prevent abnormalities in the rumen Small particle size of starter can result

in the buildup of the keratin layer on rumen papillae (McGavin and Morrill 1976 Greenwood et

al 1997 Beharka et al 1998) which has been shown to reduce VFA absorption (Hinders and

Owen 1965) and could potentially influence intake Hence the requirement for forage and with it

calvesrsquo intake behavior response is most likely dependent on starter fermentability particle size

and intake level

Conclusions

With all the factors that affect the intake behavior response to adding forage to young calf

diets it is understandable that there are some discrepancies in the reported literature Starter

ingredient composition particle size and intake level are necessary to make a recommendation as

to when forage should be fed and these will change with different management practices

Heinrichs and Jones (2003) suggested that forage should be fed to calves when starter

consumption reaches 23 to 27 kgd at around 6 to 7 wk of age However this recommendation is

for textured starter with coarsely processed grains and should not apply for a high starch pelleted

starter where particle size of grain is fine Pelleted starters with high amounts of ruminally

digestible starch will need a forage source much sooner than coarse grain starters The present

13

analysis of literature was limited by studies not reporting data about the physical nature of starter

and nutrient composition as has been suggested by Kertz and Chester-Jones (2004) The amount

of starch and particle size in starter will impact the behavioral response of calves to forage intake

and should always be reported when these variables are being analyzed bedding will also affect

the observations and its impact should be considered when making conclusions

14

References



641215ndash1226

Bach A A Gimeacutenez J L Juaristi and J Ahedo 2007 Effects of physical form of a starter for

dairy replacement calves on feed intake and performance J Dairy Sci 903028ndash3033

Beharka A A T G Nagaraja J L Morrill G A Kennedy and R D Klemm 1998 Effects of

form of the diet on anatomical microbial and fermentative development of the rumen of

neonatal calves J Dairy Sci 811946ndash1955

Brownlee A 1956 The development of rumen papillae in cattle fed on different diets

BritVetJ 112 369-375



Castells L A Bach G Araujo C Montoro and M Terreacute 2012 Effect of different forage

sources on performance and feeding behavior of Holstein calves J Dairy Sci 95286ndash

293

Castells L A Bach A Aris and M Terreacute 2013 Effects of forage provision to young calves on

rumen fermentation and development of the gastrointestinal tract J Dairy Sci 965226ndash

5236

Corona L S Rodriguez R A Ware and R A Zinn 2005 Comparative effects of whole

ground dry-rolled and steam-flaked corn on digestion and growth performance in

feedlot cattle Prof Anim Sci 21200ndash206

Coverdale J A H D Tyler J D Quigley and J A Brumm 2004 Effect of various levels of

forage and form of diet on rumen development and growth in calves J Dairy Sci

872554ndash2562

Cummins K A J E Nocek and C E Polan 1982 Growth and nitrogen balance of calves fed

rations of varying nitrogen degradability and physical form J Dairy Sci 65773ndash783

Davis C L and J K Drackley 1998 The development nutrition and management of the

young calf Iowa State University Press Ames Iowa

De Brabander D L J L De Boever J M Vanacker CH V Boucqueacute and S M Botterman

1999 Evaluation of physical structure in dairy dairy cattle nutrition Pages 111ndash145 in

Proc Recent Advances in Animal Nutrition P C Garnsworthy and J Wiseman eds

Nottingham UK



15

Fokkink W B T M Hill H G Bateman J M Aldrich R L Schlotterbeck and A F Kertz

2011 Case Study Effect of high- and low-cereal-grain starters on straw intake and rumen

development of neonatal Holstein calves Prof Anim Sci 27357ndash364

Greenwood R H J L Morrill E C Titgemeyer and G A Kennedy 1997 A new method of

measuring diet abrasion and its effect on the development of the forestomach J Dairy

Sci 802534ndash2541

Heinrichs A J and C M Jones Feeding the newborn dairy calf 2003 The Pennsylvania State

University

Hibbs J W H R Conrad W D Pounden and N Frank 1956 A high roughage system for

raising calves based on early development of rumen function VI Influence of hay to

grain ratio on calf performance rumen development and certain blood changes J Dairy

Sci 39171ndash179

Hibbs J W W D Pounden and H R Conrad 1953 A high roughage system for raising calves

based on the early development of rumen function I Effect of variations in the ration on

growth feed consumption and utilization J Dairy Sci 36717ndash727

Hill T M H G Bateman II J M Aldrich and R L Schlotterbeck 2008 Effects of the

amount of chopped hay or cottonseed hulls in a textured calf starter on young calf

performance J Dairy Sci 912684ndash2693

Hinders R G and F G Owen 1965 Relation of ruminal parakeratosis development to volatile

fatty acid absorption J Dairy Sci 481069ndash1073

Jahn E P T Chandler and C E Polan 1970 Effects of fiber and ratio of starch to sugar on

performance of ruminating calves J Dairy Sci 53466ndash474

Kertz A F and H Chester-Jones 2004 Invited review Guidelines for measuring and reporting

calf and heifer experimental data J Dairy Sci 873577ndash3580

Khan M A D M Weary and M A G von Keyserlingk 2011 Hay intake improves

performance and rumen development of calves fed higher quantities of milk J Dairy Sci

943547ndash3553

Kincaid R L 1980 Alternate methods of feeding alfalfa to calves J Dairy Sci 6391ndash94

Krause K M and G R Oetzel 2006 Understanding and preventing subacute ruminal acidosis

in dairy herds A review Anim Feed Sci Technol 126215ndash236

Laarman A H T Sugino and M Oba 2012 Effects of starch content of calf starter on growth

and rumen pH in Holstein calves during the weaning transition J Dairy Sci 954478ndash

4487

Lesmeister K E 2003 Dietary alterations and their influence on rumen development in neonatal

dairy calves Thesis The Pennsylvania State University University Park PA

16

Lesmeister K E and A J Heinrichs 2004 Effects of corn processing on growth characteristics

rumen development and rumen parameters in neonatal dairy calves J Dairy Sci

873439ndash3450

Maulfair D D K K McIntyre and A J Heinrichs 2013 Subacute ruminal acidosis and total

mixed ration preference in lactating dairy cows J Dairy Sci 966610ndash6620

McGavin M D and J L Morrill 1976 Scanning electron microscopy of ruminal papillae in

calves fed various amounts and forms of roughage Am J Vet Res 37497ndash508

NRC 2001 Nutrient Requirements of Dairy Cattle 7th ed Natl Acad Press Washington DC

Phillips C J C 2004 The effects of forage provision and group size on the behavior of calves J

Dairy Sci 871380ndash1388

Porter J C R G Warner and A F Kertz 2007 Effect of fiber level and physical form of

starter on growth and development of dairy calves fed no forage Prof Anim Sci

23395ndash400









Terreacute M E Pedrals A Dalmau and A Bach 2013 What do preweaned and weaned calves

need in the diet A high fiber content or a forage source J Dairy Sci 965217ndash5225

Thomas D B and C E Hinks 1982 The effect of changing the physical form of roughage on

the performance of the early-weaned calf Anim Prod 35375ndash384



Univ Ithaca NY


the animals stomach J Agr Food Chem 4788ndash792

Warner R G J C Porter and S T Slack 1973 Calf starter formulation for neonatal calves fed

no hay Pages 116ndash122 in Proc Cornell Nutr Conf Cornell Univ Ithaca NY

Zinn R A F N Owens and R A Ware 2002 Flaking corn processing mechanics quality

standards and impacts on energy availability and performance of feedlot cattle J Anim

Sci 801145ndash1156

17

Chapter 3

Whole oats in calf starters

Abstract

A series of 3 trials were conducted to determine effects of whole or ground oats in starter

grain on reticulorumen fermentation and digestive system development of pre-weaned calves

Male Holstein calves (431 plusmn 23 kg at birth n = 8 9 and 7 for trials 1 2 and 3 respectively)

were housed in individual pens in a heated facility bedding was covered with landscape fabric to

avoid consumption of bedding In trials 1 and 2 calves were fitted with a rumen cannula by wk 2

of life In all trials a fixed amount of starter (containing 25 oats either ground and in the pellet


randomly assigned to all pelleted starter or pellets plus whole oats Rumen contents (trials 1 and

2) were sampled weekly at -8 -4 0 2 4 8 and 12 h after grain feeding for pH and volatile fatty

acid determination Calves were euthanized 3 wk (trial 1) or 4 wk (trials 2 and 3) after grain was

available organs were harvested emptied rinsed and weighed to gauge digestive organ

development Starter intake was not different between treatments Weekly measurements of








18



oats did not affect rumen fermentation nor did it improve digestive system development

Key words calf rumen fermentation whole oats

Introduction

A large variety of feedstuffs can be fed to neonatal dairy calves In addition to diverse

nutritive values feed sources can be offered in various forms to provide differing physical and

digestive functions in calf starters The National Research Council (NRC 2001) suggests calves

be restrained from eating long hay before weaning but recommends providing feed with

sufficient coarseness to avert impaction of particles between rumen papillae and prevent

abnormal papillae growth Previous studies have shown that diets where all ingredients were

ground increased papillae keratinization and incidence of abnormal shape compared with diets

greater in particle size (Greenwood et al 1997 Beharka et al 1998) Feeding starter in a coarse

mash form vs ground and pelleted increased DM digestibility at 8 wk of age reduced the age at

which calves started ruminating and increased time spent ruminating (Porter et al 2007) Longer

time spent ruminating increases saliva production which increases rumen buffering (Krause and

Oetzel 2006) Higher rumen pH in response to greater particle size has been observed in diets

containing hay (Greenwood et al 1997 Beharka et al 1998) Effects of particle size in calf

starters on rumen fermentation have been previously studied but starters had hay (Greenwood et

al 1997 Beharka et al 1998) calves had access to eat bedding (Lesmeister and Heinrichs

2004) or fermentation was measured only at slaughter (Porter et al 2007) Hay in the starter and

19

bedding intake are confounding factors when assessing effects of grain particle size Whole oats

are about 1027 mm in length (Doehlert et al 2006) which is greater than the threshold particle

size for particles leaving the rumen in adult cattle and sheep (Maulfair et al 2011) Thus whole

oats must be mechanically broken down by chewing which should increase time spent chewing

and slow the rate at which oat starch is available to rumen microbes resulting in a more stable

rumen environment and providing the necessary abrasion to prevent the buildup of keratin on the

rumen epithelium

The objective of this study was to evaluate whether increasing calf starter particle size by

providing whole oats would affect rumen pH rumen fermentation and development of the

digestive system A secondary objective was to observe the kinetics of rumen fermentation at an

early age

We hypothesized that whole vs ground oats in the starter would enhance rumen

development by providing a longer feed particle size that would improve digestion and rumen

papillae growth

Materials and methods

Protocols for this study were approved by The Pennsylvania State University Institutional

Animal Care and Use Committee under IACUC 41010 Three studies were done as part of this

experimental protocol

In trial 1 Holstein bull calves (n = 10) purchased from a single commercial herd were

removed from their dam inmediately after birth weighed and fed 36 L of pooled colostrum

within 1 h of birth Calves were then transported for 20 min to the experimental housing facility

where they were fed an additional 18 L of colostrum 6 to 8 h after the first feeding Housing

20

consisted of individual pens that were 21 times 16 m inside a mechanically ventilated heated

facility bedding was covered with landscape fabric to avoid consumption of bedding Water was

offered free choice and a medicated (Decoquinate 3080 gton) milk replacer powder containing

20 CP and 20 fat (Provimi North America Brookville OH) and reconstituted to 13 DM

was fed at 12 of birth BW divided in 2 equal feedings per d at 8000 and 1930 h All calves were

ruminally fistulated with 28-mm (id) rubber cannulae by the second wk of age when they were

randomly assigned to treatments an all pelleted starter with ground oats in the pellet (G) or

pellets plus whole oats (W Table 3-1) Starters differed only in oats processing with all

ingredients coming from the same batch a single batch of each starter was prepared and used for

all 3 trials Calf starter was fed once daily at 2000 h after milk replacer feeding Amount of

starter offered was adjusted with age and was based on average intakes of calves fed similar milk

replacer diets To equalize intake calves were fed a fixed amount of starter orts when present

were placed in the rumen through the cannula at 2000 h Health was monitored twice daily and

sick calves were treated per veterinary recommendation

Rumen contents were sampled 1 dwk starting 1 wk after starter was offered at -8 -4 0

2 4 8 and 12 h after starter feeding Contents (about 40 mL) were strained through 2 layers of

cheese cloth and pH of the fluid fraction was immediately determined with a handheld pH meter

(pHTestr 10 Eutech Instruments Vernon Hills IL) Rumen fluid (5 mL) was then placed into

tubes containing 1 mL of 25 metaphosphoric acid and 1 mL of 6 2-ethyl butyric acid (internal

standard) and stored at -20degC until analyzed for VFA and NH3 Feces were collected from the

landscape fabric over a 22-h period at the time of rumen sampling and stored at -20degC for later

analysis

A xylose absorption test was conducted when grain feeding began and weekly thereafter

D-xylose (Alfa Aesar Ward Hill MA) was administered in the morning milk replacer at 05 gkg

of BW Blood samples were taken before and 4 h post xylose administration via jugular

21

venipuncture into evacuated tubes containing anticoagulant (K2 EDTA Becton Dickinson and

Company Franklin Lakes NJ) Blood was centrifuged at 3600 times g for 15 min and plasma was

stored at -20degC until analysis

At 5 wk of age (3 wk of grain feeding) calves were killed via captive bolt stunning and

exsanguination Reticulo-rumens omasums and abomasums were collected emptied rinsed with

cold water drained of excess water dissected and weighed Livers and spleens were collected

rinsed with cold water drained of excess water and weighed Reticulorumen contents were

strained through 2 layers of cheese cloth the solid fraction was stored at -20degC until analyzed for

particle length The small intestine was sampled at approximately 20 cm from the pylorus

(duodenum) at its estimated midpoint (jejunum) and 20 cm from cecum (ileum) samples were

immediately rinsed with ice-cold physiological saline and stored in 10 neutral buffered formalin

(Azer Scientific Inc Morgantown PA)

In Trial 2 calves (n = 10) received the same management practices and measurements as

in Trial 1 with the exception that the trial was extended for 1 wk so calves were killed at 6 wk of

age after 4 wk of starter feeding Milk replacer powder contained 20 CP and 20 fat and was

medicated (Decoquinate 454 gton Renaissance Nutrition Roaring Spring PA) A subsample of

feces (10 g) from every fecal deposition during sampling was immediately analyzed for pH after

it was mixed in equal amounts (wtwt) of distilled water

In Trial 3 calves (n = 8) received the same management practices as in Trial 1 with the

exception that calves were not fistulated starter feeding began at 3 wk of age and calves were

killed at 7 wk of age (4 wk of starter feeding) Milk replacer powder contained 20 CP and 20

fat (US Feeds Eldora IA) and decoquinate (Deccox-M Alpharma Bridgewater NJ) was added

to milk replacer at about 32 gton Feces were analyzed for pH as in Trial 2

Sample analyses

Samples of manufactured pellets were collected from every second bag (227 kg) at the

time of manufacturing and composited before whole oats and pellets were mixed for W starter

Pellet samples and whole oats were analyzed (AOAC 2000) for DM (oven method 93015) ash

(oven method 94205) CP (Kjeldahl method 98805) fat (diethyl ether extraction method

200305) and Ca and P (dry ashing acid digestion analysis by inductively coupled plasma

spectroscopy method 98501) Additionally NDF with ash concentration by the procedure of

Van Soest et al (1991) without sodium sulfite or α-amylase and ADF with ash concentration

(Robertson and Van Soest 1981) were quantified Starch was analyzed with correction for free

glucose as described in Hall (2009) A portion of each fecal sample was dried in a forced air oven

at 55degC for 72 h to determine DM and starch content Feces were gelatinized with sodium

hydroxide for starch concentration analysis as described by Karkalas (1985) using an enzymatic

method

Xylose concentration in plasma was analyzed as described by Merritt and Duelly (1983)

absorption was calculated by the difference before and after xylose administration After thawing

rumen fluid was centrifuged 3 times at 4000 times g for 30 min at 4degC to obtain a clear supernatant

which was analyzed for NH3 according to Chaney and Marbach (1962) Supernatant was filtered

through a 045-microm polypropylene membrane before being analyzed for VFA molar concentration

by gas chromatography (Yang and Varga 1989)

Particle size distribution of feces and the solid fraction of reticulo-rumen contents was

analyzed via the wet-sieving technique of Maulfair and Heinrichs (2010) using screen sizes of

015 0425 06 085 10 118 and 335 mm (VWR Arlington Heights IL) Starters were

submerged in hot water for 10 min before sieving The fraction that passed through the 015-mm

23

screen was considered soluble Data were analyzed considering percentage of DM of each

particle fraction retained on screens ge 015 mm (retained) and including the soluble fraction

(total) Geometric mean particle length (Xgm) was calculated (ASABE 2007) with particles

retained on the top screen assumed to be 47 mm long (square-hole diagonal of top screen)

Reticulo-rumen dissection and measurement of rumen papillae and wall thickness

followed Lesmeister et al (2004) with 8 papillae measured per sample (40area) and rumen wall

thickness measured twice per sample (10area) Formalin-fixed intestinal samples and a sample

from the left side of the cranial ventral sac of the rumen were embedded in paraffin sliced and

stained with hematoxylin and eosin Villus length and crypt depth of intestinal samples were

evaluated using a measuring reticule fitted on the eyepiece mean villus height and crypt depth

came from 20 well oriented crypt-villus units from each intestinal section Papillae shape and

keratin layer were determined in rumen slides A 0 to 5 scale with 0 being nonexistent and 5

maximum thickness was used for keratin layer Each calf was categorized as having either normal

or abnormal papillae based on the shape of the majority of papillae blunted and arborized

papillae were considered abnormal tongue shape papillae were considered normal

Statistical analyses

Data were analyzed using the MIXED procedure in SAS (Version 94 SAS Institute

Inc Cary NC) as a completely randomized block design with trial as block Calf within

treatment was a random effect used to test the fixed effect of treatment block was a fixed effect

and its interaction with treatment was tested in the model Fixed effect of time and its interactions

with other fixed effects were included in the model when multiple observations occurred between

weeks (day for intake) and within sampling day Repeated measures assuming heterogeneous

compound symmetry covariance structure were used for fecal pH and fecal starch variance

24

components covariance structure was used for fecal particle size and xylose data and

autoregressive variance components covariance structure for intake Goodness of fit criteria were

used to select covariance structures for variables Packed cell volume () was tested as a

covariate for xylose absorption but not included because it was not significant Spatial (power)

covariance structure [SP(POW)] was used for rumen fermentation data because of unequally

spaced data the distance between sampling points over the day was uneven Linear and quadratic

contrasts for time after grain feeding between weeks and within sampling day were tested using

the CONTRAST statement Chi-square with the Fisher exact test was used to analyze papillae

shape Least square means are presented in tables and evidence for statistical significance was

declared at P le 005 with trends at P le 010

Results and discussion

One calf from Trial 1 was eliminated from data analysis because of excessive leaking

from the rumen fistula 2 calves were eliminated from Trials 1 and 3 due to scours and in Trial 2

one calf died from peritonitis The number of calves used for analyses in each trial is reported in

Table 3-2 Ingredient composition of starter grain (Table 3-1) differed only in oats processing

and chemical composition was similar between diets Oats processing influenced the particle size

of starters the proportion of particles on the top sieve for W was greater as expected

compensated by a lower proportion in the soluble fraction When combined these changes made

Xgm of W about 50 larger than that of G The proportion of particles gt 118 mm in G was

lower than the recommended particle size (50 of particles gt 119 mm) for calves fed starter with

no forage and without access to consume bedding to ensure adequate intake proper rumen

fermentation (Warner et al 1973) prevent physiological abnormalities and initiate rumination

(Porter et al 2007) The percentage of particles gt 118 mm in W was 60 greater than that of G

25

hence particle size was expected to have a large impact on rumen fermentation and rumen

development parameters

Total starter intake (Figure 3-1) calculated as voluntary plus orts put through the

cannula was similar between treatments and increased with time by design The difference

between voluntary intake and total intake increased by day and was likely in response to the

amount of starter put through the cannula Figure 3-2 compares voluntary intake between trials

From 1 to 21 d no difference was detected between trials but between 22 and 28 d voluntary

intake of non-cannulated calves (Trial 3) increased while intake of cannulated calves decreased

(Trial 2) Voluntary intake in Figure 3-1 was affected by intake in Trial 3 where calves were not

cannulated so the decline observed in Trial 2 (Figure 3-2) was not detected and instead voluntary

intake leveled up to 27 d The intake drop on d 21 is because calves in Trial 1 were harvested on d

22 so time for voluntary intake was reduced and no starter was put through the cannula

Likewise there is no data for total intake on d 28 and voluntary intake declined Since total intake

for cannulated calves between treatments was equal the difference between treatments after 21 d

comes from Trial 3 where though the difference was not statistically significant calves on G had

greater intake than calves on W (658 plusmn 63 vs 567 plusmn 54 gd plusmn SE) Numeric intake differences in

Trial 3 did not impact rumen fermentation parameters because calves in that trial were not

cannulated

Rumen fermentation

Rumen pH was not affected by diet and decreased linearly with age (Table 3-3) The

decline in rumen pH with age is consistent with Beharka et al (1998) where pH decreased until

wk 8 of age This decrease in pH with age is a response of increased starter intake Figure 3-3

shows pH variation over time after grain feeding a nadir is reached at approximately 4 h after

26

feeding for wk 1 to 3 and at 8 h for wk 4 By 2 h post-prandium (PP) rumen pH had fallen by

approximately 15 pH units in wk 2 and 3 and 1 unit in wk 4 which is an increase in acidity of

42 57 30 and 10 fold (Covington et al 1985) compared to pre-prandial levels for wk 1 through

4 respectively The 2 h PP increase in acidity decreased with age even when starch intake at

sampling d increased from about 50 g in wk 1 to 124 217 and 325 g in wk 2 3 and 4

respectively This is likely because rumen fluid buffering capacity increases with age and at low

pH levels VFA contribute to rumen buffering (Williams and Frost 1992) However the dramatic

change in acidity likely affected microbial populations (particularly pH-sensitive flora such as

cellulolytic fermenters Slyter 1986 Anderson et al 1987) morphological changes in epithelial

structure (Steele et al 2009 2011a) and expression of genes involved in short chain fatty acid

metabolism and cholesterol homeostasis in the rumen epithelium (Steele et al 2011b) During

wk 4 pH was lt 55 most of the time and lt 5 for over 10 hd which in adult cattle is considered

acute ruminal acidosis and can lead to fatal consequences (Krause and Oetzel 2006) Calves in

this study did not show signs of metabolic disorders which suggests that at this age calves appear

to tolerate pH levels that would be detrimental for adult cattle health A possible explanation for

this resilience is that the rumen of the young calf in relation to its body size is smaller than in

adult cattle and its capacity for absorption has not fully developed Hence the production and

absorption of endotoxins that negatively affect adult cattle with acidosis as reviewed by Plaizier

et al (2012) does not appear to be enough to compromise calf health If absorptive capacity

depended only on papillae length calves in this study would have had just 10 to 14 of the

absorptive capacity of an adult animal Papillae length averaged 071 mm compared to a

maximum length in mature cattle of between 5 and 7 mm (Huber 1969) Nevertheless potential

carryover effects of low pH on later productivity and health cannot be determined from this study

It should be noted that there is the possibility that low pH may be beneficial to rumen

development as low pH might stimulate rumen epithelial cell proliferation (Laarman et al

27

2012) The pH levels in wk 4 were lower than those previously reported (Beharka et al 1998

Lesmeister and Heinrichs 2004 Khan et al 2008 Laarman et al 2012) which is possibly a

combination of high starch levels and small particle size lack of forage in the diet and no access

to bedding material for consumption in the present study Feeding orts through the cannula may

have also contributed to low pH as voluntary intake decreased with time and orts were

introduced once a day only which may have overwhelmed rumen buffering capacity Starter

introduced through the cannula was not chewed so it did not contribute to the flow of saliva to

the rumen This may have further reduced buffering capacity as saliva contains large amount of

buffering compounds (Krause and Oetzel 2006) The lack of differences in rumen pH between

treatments is contrary to our hypothesis We expected W to have a more stable pH than G because

of its greater particle size and slower fermentation of starch in the rumen Greenwood et al

(2007) found greater particle size of starter resulted in higher rumen pH possibly via an increase

in the time calves spent ruminating as particle size increased (Hodgson 1971) thereby affecting

saliva production and rumen buffering (Krause and Oetzel 2006) Calves eating a starter with

whole corn had higher pH than those fed processed corn (Lesmeister and Heinrichs 2004)

Whole oats would need to be chewed for their starch to be available which would decrease

rumen-available starch at the time of eating Particle size of rumen contents at slaughter (Table 3-

4) 12 to 16 h after grain feeding was greater for W evidence that some oats had not been broken

down by chewing and suggesting that lack of effects in rumen pH in spite of differences in

particle size could be due to particle size effects being overshadowed by high starch content of

starters Oats accounted for about 31 of total starch in starter or about 12 percentage units of

starter DM Corn processing affected rumen pH in the Lesmeister and Heinrichs (2004) study

when it accounted for 33 of starter DM and about 75 of the 31 starch in the starter

(assuming corn contained 70 starch) Thus it is possible that in the present study the 31

28

percentage units of starch in starter provided by the pellets in W diet overwhelmed the effects of

whole oats

Low rumen pH is a consequence of acid production exceeding the capacity of absorptive

mechanisms to clear VFA from the rumen buffering capacity (particularly saliva produced

during cud chewing) and outflow of acids from the rumen Rapid fermentation of starches and

sugars in starters clearly overwhelmed the limited ability of these neonates to maintain rumen pH

Although there were no visible consequences of acute acidosis that occurred in the rumens of

these calves the long-term effects of continuous low rumen pH in calves are yet to be

determined In adult cattle acidosis has long-term consequences leading to laminitis and abscesses

in the kidneys liver heart and lungs and it has been associated with bacterial pneumonia (Klein

et al 2003)

Total rumen VFA did not differ by diet but there was a diet by wk interaction where G

tended (P = 006) to have higher VFA concentration in wk 2 The effect of starter particle size on

rumen VFA is inconsistent some researchers have observed greater VFA concentration with

smaller particle size (Beharka et al 1998 Coverdale et al 2004) while others have not detected

a difference (Greenwood et al 1997) The quadratic effect of age on total VFA observed in this

study differs from other studies where VFA concentration continually increased to the end of the

trial at 10 wk (Anderson et al 1987) 8 wk (Beharka et al1998) and 6 wk (Lesmeister and

Heinrichs 2004) The lower VFA concentration at wk 4 compared to wk 3 is possibly related to

calves having a more mature rumen epithelium capable of absorbing more VFA or a faster rumen

turnover rate It is assumed that VFA production would be greater in wk 4 due to greater starter

intake Greater VFA absorption capacity with age is also supported by the change in

concentration between 2 and 4 h PP (Figure 3-4) it went from no change at wk 1 and 2 to a drop

of about 2 and 7 at 3 and 4 wk respectively Lower rumen VFA concentration at wk 4 along

with lower pH implies that factors other than VFA concentration were influencing pH Terreacute et al

29

(2013) reported a high correlation of VFA with pH at pH gt 51 but not when pH was lt 51 and

suggested that lactic acid may also be influencing pH In adult sheep the intake of highly

digestible carbohydrates resulted in low rumen pH values that were related to high lactic acid

concentration (Briggs et al 1957) Rumen Lactobacillus counts were reported to change in a

cubic fashion with respect to calvesrsquo age however with a steady increase up to about 5 wk of age

(Anderson et al 1987) Rumen lactate concentration was not measured in this study however

the decrease in VFA concentration and pH in wk 4 suggest an increase in rumen lactic acid

concentration Molar proportions of acetate (Figure 3-5) increased with age while propionate and

butyrate decreased this is the opposite of what has been previously reported (Anderson et al

1987 Beharka et al 1998) where acetate proportion decreased while propionate and butyrate

increased Conflicting results could be due to differences in diet composition and therefore rate of

digestion as starters contained 25 alfalfa hay in those studies (Anderson et al 1987 Beharka et

al 1998) However lower fiber in this study compared with the Anderson et al (1987) and

Beharka et al (1998) studies acompanied with a decline in pH levels that would be detrimental to

fiber-digesting bacteria (Slyter 1986) suggests a decrease in acetate production Therefore the

rise in acetate concentration with time was likely responsive to changes in VFA absorption rate

which at low pH is in the order of butyric gt propionic gt acetic (Weigand et al 1972 Dijkstra et

al 1993) This is supported by changes in PP molar proportions of the 3 major VFA more

evidently with the changes at 4 wk In this wk acetate proportion increased up to 8 h PP the

same sampling point at which propionate proportion and pH reached a nadir Changes in butyrate

concentration are subtle as its proportion was consistently under 5 Hence differences in molar

percentages of individual VFA with age between this study and the Anderson et al (1987) and

Beharka et al (1998) studies was a result of lower rumen pH in this study Similar PP changes in

VFA molar proportions were reported in sheep fed diets high in starch which depressed rumen

pH below 5 (Reid et al 1957) In this study the only wk where pH was gt 5 at all times was wk

30

1 and only in this wk did the proportion of propionate increase while acetate decreased 2 h PP

Additionally when pH of 16-wk-old calves reached low PP levels but never below 5 acetate

decreased while propionate and butyrate increased (Quigley et al 1992) Altogether high

proportions of acetate observed in this experiment are likely a result of its accumulation which

can be expected at low pH levels and does not mean that its rate of production was not reduced

(Reid et al 1957) Iso-acid molar proportions were low and decreased with calvesrsquo age as in

previous reports (Anderson et al 1987 Beharka et al 1998)

Rumen NH3 was not different between diets but there was a diet by wk interaction

where G had higher concentration than W in wk 3 Concentration of NH3 decreased with age

which is consistent with what Lesmeister and Heinrichs (2004) observed through wk 4 Beharka

et al (1998) through wk 8 and Anderson et al (1987) through 12 wk of age In these studies this

change was attributed to an increased use of NH3 by the rumen microbial population The PP

slopes for rumen NH3 (Figure 3-6) are different from those reported by Quigley et al (1992)

where NH3 concentration rose after feeding A PP decrease in NH3 concentration is not common

as microbial proteolytic activity usually results in an increase NH3 concentration after feeding

However a PP decrease in rumen NH3 concentration was observed in steers fed diets high in

steam-flaked corn with 49 dietary starch concentration (Uwituze et al 2010) In the same study

diets with about 65 starch did not show a PP rumen NH3 drop 2 h after feeding but those diets

had gt 1 non-protein nitrogen (urea) as ingredient which likely affected rumen NH3

concentration The drop in rumen NH3 is partially related to low rumen pH as protein

degradation is reduced when pH is below 55 (Bach et al 2005) However pH values in the

Quigley et al (1992) study were also below 55 so other factors are likely responsible for

conflicting observations Diet composition may be a contributing factor starter NDF in the

Quigley et al (1992) study was 37 while in the present and Uwituze et al (2010) studies it was

31

below 20 Also starch concentration was high in the present and Uwituze et al (2010) studies

and starch can interfere with protein degradation (Bach et al 2005)

Particle size starch content and pH of feces

Particle size starch content and pH of feces are presented in Table 3-5 The Xgm of

feces was greater for W vs G when analyzed with or without the soluble fraction consistent with

a greater particle size of diet and rumen contents at slaughter for W (Table 3-4) Retained Xgm of

feces in calves fed W was 47 larger than in calves fed G when the soluble fraction was added

W was only 18 greater By comparison Xgm of W starter was 56 larger than G after adding

the soluble fraction and 50 larger when the soluble fraction was not included These

observations could be attributed to the contribution of milk replacer to the soluble fraction

However there was mechanical particle size reduction due to chewing retained Xgm of feces

was 35 and 36 lower for G and W respectively than that of starters The proportion of particles

retained on the 335-mm sieve of W was greater than the proportion retained for G and was

compensated by G having greater proportions of retained material in the lower sieves The

proportion of the soluble fraction was similar between diets Total Xgm of feces increased with

age which is consistent with a decrease of the soluble fraction this is likely due to greater

proportions of DMI coming from starter The proportion of the soluble fraction in these calves

was notably higher than those reported in heifers (Suarez-Mena et al 2013b) and lactating cows

(Maulfair et al 2011) Retained Xgm did not change with age which suggests that calves were

able to reduce particle size of starter to a similar degree as starter intake increased

No difference was detected in fecal pH (Figure 3-7) although it was numerically higher

for W treatment Fecal pH decreased with age which is consistent with rumen pH decreasing

with age and in response to increasing amounts of starter intake Starch content of feces was

32

higher for W vs G this is in response to some oats in W passing through the digestive tract

unbroken which is confirmed by the greater proportion of fecal particles retained on the top

screen for W Allen (2011) observed that when diets contained either whole or steam-flaked corn

starch content of feces was similar pre-weaning but greater for the diet containing whole corn

post-weaning Greater starch concentration in feces suggests a lower digestibility of whole grains

indeed when Porter et al (2007) compared DM digestibility of mash vs pellet starters they

observed that the mash starter had greater digestibility Fecal starch content increased with age

which is comparable to the Allen (2011) study where weaned calvesrsquo feces had higher amounts of

starch compared to pre-weaned calves This is likely a result of greater starter intake increasing

the rate of passage however low rumen pH could have affected starch digestion in the small

intestine Starch is digested in the rumen and absorbed as VFA Starch that bypasses ruminal

fermentation is either digested enzymatically in the small intestine and absorbed as less complex

sugars or digested in the large intestine and absorbed as VFA Wheeler and Noller (1977)

measured pH across the digestive tract of ruminants fed high grain rations and determined that

fecal pH is a reliable measure for intestinal pH In the present study the fecal pH distance from

the optimal pH for pancreatic amylase activity (69 Russell et al 1981) increased with calf age

It is possible that low rumen pH negatively influenced the acidity of digesta leaving the

abomasum which overwhelmed the small intestinal buffering capacity (Harrison and Hill 1962

Wheeler and Noller 1977) decreasing pancreatic amylase activity and the digestibility of starch

By wk 4 fecal pH was 62 which in the small intestine would mean a 30 reduction in pancreatic

amylase activity (Russell et al 1981) In adult cattle a grain-based SARA challenge increased the

amount of starch bypassing rumen fermentation increasing the concentration of free LPS (Li et

al 2012) which can negatively impact cattlersquos health (Plaizier et al 2012) Thus the rise in

fecal starch content observed with calvesrsquo age in this study could potentially have a negative

effect on calf health

33

Digestive organ measurements

Slaughter measurements and rumen development parameters are presented in Table 3-6

Reticulorumen weight tended to be greater for G vs W however this difference was not

statistically significant when analyzed as percent of BW Papillae length tended to be greater for

G vs W consistent with a heavier reticulorumen Similar results were observed by Greenwood et

al (1997) where papillae length decreased as particle size of starter diets increased although no

differences were detected in reticulorumen weight Longer papillae for shorter particle size

contrasts with findings by Beharka et al (1998) where feeding a ground diet resulted in shorter

papillae in the dorsal and dorsal blind sacs than an unground diet A possible explanation for this

discrepancy is the length of time calves were kept on experimental diets about 11 wk in Beharka

et al (1998) 6 wk in Greenwood et al (1997) and 3 or 4 wk in the present study Sampling

location and measuring method are also inconsistent among studies which could also contribute

to discrepancies Longer papillae could be attributed to more available nutrients for fermentation

due to an increase in surface area with shorter grain particle size this is supported in the present

study by reduced fecal starch content in G However rumen fermentation data does not support

this hypothesis as it was similar between diets An alternative explanation is that the lack of

abrasion in G permitted excessive keratinization of rumen epithelium and papillae grew longer to

compensate for the loss of absorptive surface area McGavin and Morrill (1976) proposed that

branching of rumen papillae is in compensation for a loss of absorptive capacity in response to

thickening of the keratin layer The secondary hypothesis of this study is based on the same

principle and the Greenwood et al (1997) observation that papillae length increased along with

percent of keratin in epithelium A thickening of the keratin layer in the rumen epithelium with

34

decreased starter particle size was observed by Strusinska et al (2009) in 90-d-old calves even

when calves on ground grain had access to hay and in the last 2 wk of age all calves had access

to hay In the present study keratin layer and papillae shape were evaluated but statistically

significant differences were not detected however numerical trends are in agreement with

Greenwood et al (1997) findings A score was assigned for keratin layer because its thickness

was highly variable across each sample making quantitative measures unreliable The scale for

scoring the keratin layer was developed from differences within the sample pool after a first

evaluation and with the purpose of comparing treatments in this study For this reason the score

of about 26 could mean that both experimental groups were affected by hyperkeratinization of

the rumen epithelium or that neither group was affected However the high percentage of calves

scored with abnormal papillae is indicative of some hyperkeratinization in both treatments

Moreover numerical differences in the proportion of calves with abnormal papillae suggest that

particle size of W did benefit the rumen Lack of a statically significant difference is possibly

related to low the number of observations in other studies where papillae shape was discussed no

statistical analysis was reported or it was not statistically different (McGavin and Morrill 1976

Greenwood et al 1997 Beharka et al 1998)

When trial 1 was analyzed by itself (Suarez-Mena et al 2013a) omasum weight was

greater for W this difference vanished when trials 2 and 3 were added to the analysis Other work

has reported greater omasum size in diets with shorter particle size (Greenwood et al 1997

Beharka et al 1998) Beharka et al (1998) attributed this observation to an increased flow of

particles with shorter particle size from rumen to omasum while Greenwood et al (1997)

credited it to greater muscular development Changes in omasum weight have been reported when

starter intake was affected either by changing starter starch source (Khan et al 2008) or milk

allowance (Suarez-Mena et al 2011) In the present study abomasum weight was greater for W

vs G increasing solid feed particle size by including forage in the diet increased abomasum

35

weight in Castells et al (2013) but had no effect in Webb et al (2013) Changing particle size by

processing had no effect on abomasum weight in the Greenwood et al (1997) and Beharka et al

(1998) studies

Crypt depth in the small intestine tended (P = 008) to be greater for G which is

consistent with a trend (P = 008) for a trial by diet interaction where villus height of G was

greater than that of W (029 vs 022 mm) in trial 3 No differences between and within diet were

detected in the different sections of the small intestine (data not shown) Our results contrast with

those reported by Strusinska et al (2009) where feeding whole grain positively influenced small

intestine morphometric structure Differences in age at slaughter proportion of whole grains in

starter forage provision and intake differences between treatments in the above study may

account for the conflicting results The observations in the present study could be related to an

increased nutrient availability in the intestine for G reflected by lower starch concentration in the

feces in this treatment Xylose absorption (Table 3-2) was not different between diets and no

effect of wk was detected but a diet by wk interaction was observed where absorption for W was

greater in wk 2

Conclusions

Under the conditions of this study physical form of oats in calf starter did not affect

rumen pH and its impact on rumen VFA and NH3 concentrations over time was subtle Particle

size of starter was decreased by grinding oats and the same trend was observed in rumen contents

and fecal particle size which was greater for W Starch content of feces was greater for W

suggesting that grinding oats improved starch digestibility Reticulorumen weight and rumen

papillae tended to be larger and small intestinal crypts were deeper for G possibly due to greater

nutrient availability for that treatment Lack of effects on pH and only subtle changes in rumen

36

fermentation could be related to calves being on experimental diets for 3 and 4 wk only and the

unground fraction of W diet being only 25 thus at this level it did not add enough texture to

detect a difference Also the high starch content of the ration may have overshadowed particle

size effects however these levels were within industry standards

37

References

Allen J D 2011 Use of a near-infrared spectrophotometer to predict nutrient composition of

feces from feddlot Holstein cattle and its applicability for on-site research and industry

use PhD Diss The Univ of Arizona Tucson



641215ndash1226

AOAC 2000 Official Methods of Analysis 17th ed Association of Official Analytical

Chemists Arlington VA

ASABE (American Society of Agricultural and Biological Engineers) 2007 Method of

determining and expressing particle size of chopped forage materials by screening

ANSIASAE S424 1663ndash665 Am Soc Agric Biologic Eng St Joseph MI

Bach A S Calsamiglia and M D Stern 2005 Nitrogen metabolism in the rumen J Dairy Sci

88E9ndashE21




Briggs P K J P Hogan and R L Reid 1957 The effect of volatile fatty acids lactic acid and

ammonia on rumen pH in sheep Aust J Agric Res 8674ndash690



5236

Chaney A L and E P Marbach 1962 Modified reagents for determination of urea and

ammonia Clin Chem 8130ndash132



872554ndash2562

Covington A K R G Bates and R A Durst 1985 Definition of pH acales standard reference

values measurement of pH and related terminology (Recommendations 1984) Pure

Appl Chem 57531ndash542

Dijkstra J H Boer J Van Bruchem M Bruining and S Tamminga 1993 Absorption of

volatile fatty acids from the rumen of lactating dairy cows as influenced by volatile fatty

acid concentration pH and rumen liquid volume Br J Nutr 69385ndash396

Doehlert D C M S McMullen and J L Jannink 2006 Oat graingroat size ratios A physical

basis for test weight Cereal Chem J 83114ndash118

38



Sci 802534ndash2541

Hall M B 2009 Analysis of starch including maltooligosaccharides in animal feeds A

comparison of methods and recommended method for AOAC collaborative study J

AOAC Int 9242-49

Harrison F A and K J Hill 1962 Digestive secretions and the flow of digesta along the

duodenum of the sheep J Physiol 162225ndash243

Hodgson J 1971 The development of solid food intake in calves 1 The effect of previous

experience of solid food and the physical form of the diet on the development of food

intake after weaning Anim Prod 1315ndash24

Karkalas J 1985 An improved enzymic method for the determination of native and modified

starch J Sci Food Agric 361019ndash1027

Khan M A H J Lee W S Lee H S Kim S B Kim S B Park K S Baek J K Ha and Y

J Choi 2008 Starch source evaluation in calf starter II Ruminal parameters rumen

development nutrient digestibilities and nitrogen utilization in Holstein calves J Dairy

Sci 911140ndash1149

Kleen J L G A Hooijer J Rehage and J P T M Noordhuizen 2003 Subacute ruminal

acidosis (SARA) A review J Vet Med A 50406ndash414





4487



873439ndash3450

Lesmeister K E P R Tozer and A J Heinrichs 2004 Development and analysis of a rumen

tissue sampling procedure J Dairy Sci 871336ndash1344

Li S E Khafipour D O Krause A Kroeker J C Rodriguez-Lecompte G N Gozho and J

C Plaizier 2012 Effects of subacute ruminal acidosis challenges on fermentation and

endotoxins in the rumen and hindgut of dairy cows J Dairy Sci 95294ndash303

Maulfair D D M Fustini and A J Heinrichs 2011 Effect of varying total mixed ration

particle size on rumen digesta and fecal particle size and digestibility in lactating dairy

cows J Dairy Sci 943527ndash3536

39

Maulfair D D and A J Heinrichs 2010 Technical note Evaluation of procedures for

analyzing ration sorting and rumen digesta particle size in dairy cows J Dairy Sci

933784-3788



Merrit A M and P Duelly 1983 Phloroglucionol microassay for plasma xylose in dogs and

horses Am J Vet Res 442184ndash2185


DC

Plaizier J C E Khafipour S Li G N Gozho and D O Krause 2012 Subacute ruminal

acidosis (SARA) endotoxins and health consequences Anim Feed Sci Technol 1729ndash

21



23395ndash400

Quigley J D T M Steen and S I Boehms 1992 Postprandial changes of selected blood and

ruminal metabolites in ruminating calves fed diets with or without hay J Dairy Sci

75228ndash235

Reid R L J P Hogan and P K Briggs 1957 The effect of diet on individual volatile fatty

acids in the rumen of sheep with particular reference to the effect of low rumen pH and

adaptation on high-starch diets Aust J Agric Res 8691ndash710

Robertson J B and P J Van Soest 1981 The detergent system of analysis and its application

to human foods Pages 123ndash158 in The Analysis of Dietary Fiber in Foods W P T

James and O Theander ed Marcel Dekker Inc New York NY

Russell J R A W Young and N A Jorgensen 1981 Effect of dietary corn starch intake on

pancreatic amylase and intestinal maltase and pH in cattle J Anim Sci 521177ndash1182

Slyter L L 1986 Ability of pH-selected mixed ruminal microbial populations to digest fiber at

various pHs Appl Environ Microb 52390ndash391

Steele M A J Croom M Kahler O AlZahal S E Hook K Plaizier and B W McBride

2011a Bovine rumen epithelium undergoes rapid structural adaptations during grain-

induced subacute ruminal acidosis Am J Physiol Regul Integr Comp Physiol

300R1515ndashR1523

Steele M A G Vandervoort O AlZahal S E Hook J C Matthews and B W McBride

2011b Rumen epithelial adaptation to high-grain diets involves the coordinated

regulation of genes involved in cholesterol homeostasis Physiol Genomics 43308ndash316

40

Steele M O AlZahal S Hook J Croom and B McBride 2009 Ruminal acidosis and the

rapid onset of ruminal parakeratosis in a mature dairy cow A case report Acta Vet

Scand 5139-44

Strusinska D D Minakowski G Bomba I Otrocka-Domagala M Wisniewska and J

Tywonczuk 2009 Effect of whole cereal grains contained in the ration on calf

performance and selected morphometric parameters of the rumen and small intestine

Czech J Anim Sci 54540ndash551

Suarez-Mena F X A J Heinrichs T M Hill and C M Jones 2013a Whole oats effects on

digestive system development in neonatal dairy calves J Dairy Sci 96(E-Suppl 1)96

(Abstr)

Suarez-Mena F X T M Hill A J Heinrichs H G Bateman J M Aldrich and R L

Schlotterbeck 2011 Effects of including corn distillers dried grains with solubles in

dairy calf feeds J Dairy Sci 943037ndash3044

Suarez-Mena F X G J Lascano and A J Heinrichs 2013b Chewing activities and particle

size of rumen digesta and feces of precision-fed dairy heifers fed different forage levels

with increasing levels of distillers grains J Dairy Sci 965184ndash5193



Uwituze S G L Parsons M K Shelor B E Depenbusch K K Karges M L Gibson C D

Reinhardt J J Higgins and J S Drouillard 2010 Evaluation of dried distillers grains

and roughage source in steam-flaked corn finishing diets J Anim Sci 88258ndash274

Van Soest P J J B Robertson and B A Lewis 1991 Methods for dietary fiber neutral

detergent fiber and nonstarch polysaccharides in relation to animal nutrition J Dairy

Sci 743583ndash3597


no hay Pages 116ndash122 in Proc Cornell Nutr Conf Cornell University Ithaca NY

Webb L E E A M Bokkers L F M Heutinck B Engel W G Buist T B Rodenburg N

Stockhofe-Zurwieden and C G Van Reenen 2013 Effects of roughage source amount

and particle size on behavior and gastrointestinal health of veal calves J Dairy Sci

967765ndash7776

Weigand E J W Young and A D McGilliard 1972 Extent of butyrate metabolism by bovine

ruminoreticulum epithelium and the relationship to absorption rate J Dairy Sci 55589ndash

597

Wheeler W E and C H Noller 1977 Gastrointestinal tract pH and starch in feces of

ruminants J Anim Sci 44131ndash135

Williams P E V and A J Frost 1992 Feeding the young ruminant Pages 109ndash118 in

Neonatal Survival and Growth Occasional Publ No 15 M Varley P E V Williams

and T L J Lawrance ed Br Soc Anim Prod Edinburg UK

41

Yang C-M J and G A Varga 1989 Effect of three concentrate feeding frequencies on rumen

protozoa rumen digesta kinetics and milk yield in dairy cows J Dairy Sci 72950ndash957

42

Table 3-1 Ingredient and chemical composition and particle size of starters containing ground

oats in a pelleted feed (G) or whole oats plus a pellet (W)

Item G W

Ingredient composition DM

Ground corn 3700 3700

Ground oats1

2500 -

Whole oats1

- 2500

Soybean meal 48 CP 2446 2446

Wheat middlings 481 481

Dry molasses 300 300

Fat 200 200

Calcium carbonate 078 078

Premix2

075 075

Salt 060 060

Monocalcium phosphate 059 059

Decoquinate 6 050 050

Pellet binder 050 050

Chemical composition DM

DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578

1Contained ( of DM) 485 starch 282 NDF

2The premix contained (per kilogram) 160 g Cu 013 g Co 940 g Fe 014 g I 54 g Mn 004 g

Se 670 g Zn 1800 IU vitamin A 600 IU vitamin D 16 IU vitamin E 001 g biotin 293 g

cobalamin 004 g folic acid 177 g niacin 132 g pantothenic acid 024 g pyridoxine 030 g

riboflavin and 029 g thiamin (Provimi North America Brookville OH)

43

3Geometric mean (Xgm) and standard deviation (Sgm) of particle length as calculated by ASABE

(2007) using data from screens ge 015 mm Particles retained on the top screen were assumed to

be 47 mm long


(2007) using data from all particle fractions Particles retained on the top screen were assumed to

be 47 mm long

5Cumulative proportion of retained particles over a 118-mm sieve

44

Table 3-2 Description of calves fed starters containing ground oats in a pelleted feed (G) or

whole oats plus a pellet (W)

Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-

BW at birth kg 433 428 07

058

BW at slaughter kg 604 594 13

057

45

Table 3-3 Rumen fermentation of calves fed starters containing ground oats in a pelleted feed (G) or whole oats plus a pellet (W)

P-value

1Wk

Wk

1 SE 2 SE 3 SE 4 SE Diet DietWk Linear Quadratic

Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897

Individual VFA mol100 mol

Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009

1From the time after starter was available

46

Table 3-4 Rumen contents particle size of calves fed starters containing ground oats in a pelleted feed (G) or whole oats plus a pellet (W)

Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001

1Geometric mean (Xgm) and standard deviation (Sgm) of particle length as calculated by ASABE (2007) using data from screens ge 015 mm

Particles retained on the top screen were assumed to be 47 mm long

47

Table 3-5 Fecal particle size and xylose absorption of calves fed starters containing ground oats in a pelleted feed (G) or whole oats plus a

pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269

1From the time starter was available



3Geometric mean (Xgm) and standard deviation (Sgm) of particle length as calculated by ASABE (2007) using data from all particle fractions


4Proportion of particles that passed through the bottom screen

49

Table 3-6 Digestive system development measurements in calves fed starters containing ground


Diet P-value

G SE W SE

Calves n 11 - 13 -

Slaughter measurements

Carcass kg 453 10 444 09

052

Reticulorumen g 569 24 503 22

006

Omasum g 126 9 126 8

097

Abomasum g 240 9 274 8

001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW

Reticulorumen 093 004 085 004

015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen

Papillae length mm 075 003 068 003

009

Papillae width mm 051 001 048 001

011

Rumen wall thickness mm 083 004 078 003

033

Abnormal papillae 1 5455 - 3846 -

068

Keratin layer score2 272 040 250 036

069

Small intestine

Villus height mm 048 002 045 002

023

Crypt depth mm 027 001 024 001 008

1Proportion of calves in which papillae were considered with abnormal shape blunted and

arborized

2The keratin layer was scored with 0 being nonexistent and 5 maximum thickness

50

Figure 3-1 Starter intake of calves fed ground (G) or whole (W) oats in the starter Data comes

from 3 trials with 8 9 and 7 calves for trials 1 2 and 3 respectively Calves in trials 1 and 2 were

fitted with rumen cannulas and calves in trial 1 were slaughtered on d 22 Total starter intake (T)

is the cumulative of voluntary intake (V) plus starter introduced through rumen cannulae Diet

effect for voluntary and cumulative intakes (P gt 01)

51

Figure 3-2 Mean voluntary starter intake of calves fed ground or whole oats in starter Data

comes from 3 trials with 8 9 and 7 calves for trials 1 (solid line) 2 (- - -) and 3 ()

respectively Calves in trials 1 and 2 were fitted with rumen cannulae and orts from their daily

starter allotment were put through the cannula that starter is not reflected in this figure Trial

effect up to d 21 (P gt 010) trial effect d 22 to 28 (P lt 001) trial by diet interaction (P gt 010)

52

Figure 3-3 Mean rumen pH variation at -8 -4 0 2 4 8 and 12 h relative to feeding from 1 to 4

wk after starter was available for calves fed ground or whole oats in the starter (n = 17 up to wk 3

and 9 in wk 4) Linear effect for wk (P lt 001) cubic effect for time relative to feeding (P lt 001)

53

Figure 3-4 Mean rumen VFA concentration at -8 -4 0 2 4 8 and 12 h relative to feeding from

1 to 4 wk after starter was available for calves fed ground or whole oats in the starter (n = 17 up

to wk 3 and 9 in wk 4) Quadratic effect for wk (P lt 001) cubic effect for time relative to

feeding (P lt 001)

54

Figure 3-5 Mean rumen acetate propionate and butyrate molar percentage of total VFA at -8 -

4 0 2 4 8 and 12 h relative to feeding for wk 1 to 4 after starter was available for calves fed

ground or whole oats in the starter (n = 17 up to wk 3 and 9 in wk 4) Acetate and butyrate cubic

effect for time relative to feeding (P lt 005) Propionate effect for time relative to feeding linear

(P = 006) and cubic effect (P = 015)

55

Figure 3-6 Mean rumen NH3 concentration at -8 -4 0 2 4 8 and 12 h relative to feeding from


to wk 3 and 9 in wk 4) Linear effect for wk (P lt 001) cubic effect for time relative to feeding (P

lt 001)

56

Figure 3-7 Mean fecal pH (solid lines) and starch (dashed lines) concentration from 1 to 4 wk

after starter was available for calves fed ground (n = 11 up to wk 3 and 7 in wk 4) or whole

oats (n = 13 up to wk 3 and 9 in wk 4) in the starter Diet effect for pH (P gt 010) and starch

concentration (P lt 001) Linear effect of wk (P lt 001) for both variables Diet by wk interaction

for starch (P lt 005)

57

Appendix 1

Figure 3-8 Example of rumen papillae slides at 20times magnification scored as normal (A) and

abnormal (B) papillae

A

B

58



A

B

59

Chapter 4

Straw particle size in calf starters Effects on digestive system development and

rumen fermentation

Abstract

Two trials were conducted to determine effects of straw particle size in calf starter on

rumen fermentation and development in calves Holstein calves (n = 45) were housed in

individual pens bedding (wood shavings) was covered with landscape fabric to avoid

consumption of bedding Milk replacer was fed at 12 of birth body weightd and water offered

free choice Calves were randomly assigned to 4 treatments differing in geometric mean particle

length (Xgm) of straw comprising 5 of starter dry matter Straw was provided within the pellet

at manufacturing (PS 082 mm Xgm) or mixed with the pellet at time of feeding at Xgm of 304

(SS) 710 (MS) or 127 (LS) mm Calves (n = 12 3treatment) in trial 1 were fitted with a rumen

cannula by wk 2 of age A fixed amount of starter that was adjusted with age was offered orts

were fed through the cannula in cannulated calves Calves were euthanized 6 wk after starter was

offered (9 and 7 wk of age for trials 1 and 2) Rumen digesta pH linearly decreased with age

while volatile fatty acid concentration increased with age Overall pH had a cubic trend with SS

lower than that of PS and MS likely related to intake changes and not to treatments Molar

proportion of acetate decreased with age while propionate proportion increased Overall molar

proportions of volatile fatty acids were not affected by diet Fecal Xgm was not different in spite

of changes in diet particle size and rumen digesta of PS being greater than SS MS and LS at

slaughter Fecal pH and starch concentration were not affected by diet however pH decreased

while starch content increased with age Weight of stomach compartments rumen papillae length

60

and width and rumen wall thickness did not differ between diets Omasum weight as a

percentage of body weight at harvest linearly decreased as straw particle size increased Under

the conditions of this study modifying straw particle length in starter grain resulted in minimal

rumen fermentation parameter changes and no changes in rumen development Rumen pH and

fermentation changes with age were likely effects of increasing starter intake

Key words calf rumen fermentation starter intake

Introduction

The physical development of rumen papillae and the capacity for absorption and

metabolism of digestion endproducts by the rumen wall in the young calf are stimulated by VFA

produced by rumen fermentation rather than feed coarseness (Flatt et al 1958) Propionate and

butyrate are the most important VFA for papillae growth (Tamate et al 1962) and are products of

the fermentation of grains For this reason grains (starches) are the most important component in

a young calfrsquos diet for inducing rumen development Grains are frequently fed in a pelleted form

with fine particle size because forming a firm pellet requires fine grinding of grains (Davis and

Drackley 1998) and when pelleted concentrates are the only solid feed available papillae have

been shown to become parakeratotic exhibiting abnormal growth and compaction with fine feed

particles (McGavin and Morrill 1976) The small particle size of many all ground diets does not

provide the necessary abrasiveness to remove the keratin layer and compacted feed from the

developing rumen papillae Greenwood et al (1997) observed that keratinization of papillae was

inversely related to the dietrsquos abrasiveness when using a finely ground pelletized diet

Particle size of starter also has been shown to affect rumen fermentation Diets with

greater particle size resulted in higher rumen pH (Greenwood et al 1997 Beharka et al 1998)

61

possibly due to an increase in the time calves spend ruminating as particle size increases

(Hodgson 1971) thereby affecting saliva production which increases rumen buffering (Krause

and Oetzel 2006) Increasing starter particle size by feeding it in a coarse mash form vs ground

and pelleted reduced the age at which calves started ruminating and increased the time spent

ruminating (Porter et al 2007)

Two common ways to increase the particle size of solid feed for the young calf are to

feed a mix of whole grains or less processed grains and a supplemental pellet or to include forage

in the ration Studies by Beharka et al (1998) and Greenwood et al (1997) investigated the

effects of increasing particle size without changing diet composition at controlled DMI and

avoiding bedding consumption at inclusions of 25 alfalfa hay (Beharka et al 1998) and 15

Bromegrass hay (Greenwood et al 1997) Forage levels of 15 to 25 may be too high when

feeding low quality forage as reports have shown that when calves have ad libitum access to

straw consumption is about 4 of solid feed intake (Thomas and Hinks 1982 Castells et al

2013) Moreover Fokkink et al (2011) observed that straw intake decreased from about 4 of

solid feed intake through 5 wk of age to about 1 from 5 to 8 wk in calves that had no access to

consume bedding Hence high inclusion rates of forage (gt 10) in the pre-weaned calf diet

reduce the proportion of grains in the ration and may reduce starter intake possibly lowering the

production of VFA in the rumen which may slow down the development of the rumen epithelium

Stobo et al (1966) observed that as concentrate intake increased (by increasing its allowance)

papillae tended to be larger A small amount of forage with particle size gt 118 mm which is the

threshold particle size for particles leaving the rumen in adult cattle and sheep (Maulfair et al

2011) may satisfy the calfrsquos requirement for abrasiveness to avoid the buildup of keratin in the

rumen epithelium and maintain a more stable rumen fermentation When the particle size of

starter was evaluated in calves fed no hay and without access to consume bedding materials up to

8 wk it was determined that over 50 of particles should be larger than 119 mm to insure

62

adequate intake proper rumen fermentation (Warner et al 1973) and prevent physiological

abnormalities (Porter et al 2007)

Due to these findings this study aimed to evaluate the inclusion of a small amount of

straw (5) with different particle sizes in calf starter on rumen pH rumen fermentation and

development of the digestive system including the kinetics of rumen fermentation at an early age

We hypothesized that greater particle size of straw in the starter would enhance rumen

development by providing abrasiveness to the rumen epithelium and a more stable rumen

fermentation



Animal Care and Use Committee (IACUC 41845) Two studies were done as part of this


In Trial 1 Holstein bull calves (n = 20) purchased from a single commercial herd were

removed from their dam after birth weighed and fed 36 L of pooled colostrum within an hour of

birth Calves were then transported for 20 min to the research facility where they were fed an

additional 18 L of colostrum 6 to 8 h after the first feeding Housing consisted of individual pens

that were 21 times 16 m inside a mechanically ventilated heated facility bedding (wood shavings)

was completely covered with landscape fabric to avoid consumption of bedding thus the only

solid feed available came from treatment diets Water was offered free choice and a commercial

milk replacer powder containing 20 CP and 20 fat (US Feeds Eldora IA) and reconstituted

to 13 DM was fed at 12 of birth BW divided in 2 equal feedings per d Decoquinate (Deccox-

M Alpharma Bridgewater NJ) was added to milk replacer to feed at 05 mgkg of BW At 7 wk

of age milk replacer allowance was cut to 6 of birth BW for 1 wk before weaning Calves were

63

randomly assigned based on date and birth BW to 1 of 4 treatments differing in geometric mean

particle length (Xgm) of straw comprising 5 of starter DM Straw was provided within the

pellet (PS 082 mm Xgm) or mixed with the pellet at Xgm of 304 mm (SS) 710 mm (MS) or

127 mm (LS) at time of feeding Calves (3treatment) were ruminally fistulated with 28-mm

(id) rubber cannulas by wk 2 of life in a similar manner as Lesmeister and Heinrichs (2004)

Pellets and straw for treatments SS MS and LS were proportionally mixed for each calf daily

The 2 pellets were manufactured with all ingredients coming from the same batch and in enough

quantity for both trials Calf starter was fed once daily at 2000 h after milk replacer feeding the

amount of starter offered was adjusted with age and was based on average intakes of calves fed

similar milk replacer diets To equalize intake calves were fed a fixed amount of starter that

changed with age and was determined by previous experiences with calves on similar milk

replacer diets and by the voluntary consumption of most calves orts were fed through the cannula

in cannulated calves except during the last wk of the experiment The different lengths of straw

were obtained by chopping wheat straw and sieving it in the ASABE (2007) particle size

separator equipped with 5 screens (nominal size opening 19 127 63 396 and 117 mm for 1 to

5 respectively) and a bottom pan particles in the bottom pan were used for PS and particles

retained screens 5 4 and 3 for treatments SS MS and LS respectively Calf health was

monitored twice daily and sick calves were treated per veterinary recommendation

Rumen contents were sampled 1 dwk starting 1 wk after starter was offered (3 wk of

age) at -8 -4 0 2 4 8 and 12 h after starter feeding Contents (about 40 mL) were strained

through 2 layers of cheese cloth and pH of the fluid fraction was immediately determined with a

handheld pH meter (pHTestr 10 Eutech Instruments Vernon Hills IL) Rumen fluid (5 mL) was

then placed into tubes containing 1 mL of 25 metaphosphoric acid and 1 mL of 6 2-ethyl

butyric acid (internal standard) and stored at -20degC until analyzed for VFA and NH3 After

thawing rumen fluid was centrifuged 3 times at 4000 times g for 30 min at 4degC to obtain a clear

64

supernatant which was analyzed for NH3 according to Chaney and Marbach (1962) Supernatant

was filtered through a 045-microm polypropylene membrane before being analyzed for VFA molar

concentration by gas chromatography (Yang and Varga 1989)

A xylose absorption test was conducted to assess small intestine absorption capacity

when grain feeding began and weekly thereafter D-xylose (Alfa Aesar Ward Hill MA) was

administered in the morning milk replacer at 05 gkg of BW Blood samples were taken before

and 4 h post xylose administration via jugular venipuncture into evacuated tubes sprayed with

anticoagulant (K2 EDTA Becton Dickinson and Company Franklin Lakes NJ) Blood was

centrifuged at 3600 times g for 15 min and plasma was stored at -20degC until analysis Xylose

concentration in plasma was analyzed as described by Merritt and Duelly (1983) absorption was

calculated by the difference before and after xylose administration


exsanguination Reticulo-rumens omasums abomasums were collected emptied rinsed with




particle length

In Trial 2 calves (n = 25) from the same source received first and second colostrum

feedings before transported to the same facility as Trial 1 At arrival calves were dosed with a

capsule containing bovine coronavirus-escherichia coli antibody (First Defense Immucell

Portland ME) and 250 mg of oxytetracycline (Durvet Blue Springs MO) administered orally 5

mL of fortified vitamin B complex (Agrilabs St Joseph MO) administered subcutaneously and

3 mL florfenicol (Nuflor Intervet Summit NJ) administered intramuscularly Oxytetracycline

(250 mg) was administered every 12 h until 48 h from first dose and a second dose of florfenicol

was administered 48 h after first dose Starters were fed after am milk replacer feeding starting

65

at 6 to 8 d of life starters and straw were the same as in Trial 1 Medicated (144 gton lasalocid

Alpharma Inc Fort Lee NJ) milk replacer powder containing 20 CP and 20 fat (Provimi

North America Brookville OH) was reconstituted and fed in a similar manner and rate as in Trial

1 pm milk replacer feeding was withheld to calves that were low on starter intake and to all

calves 2 wk prior to slaughter Calves were not fistulated and feces were not collected in this trial

slaughter was done as in Trial 1 but at 6 wk after starter was first offered

Samples of manufactured pellets were collected from every second bag (227 kg)

at the time of manufacturing and composited Pellet samples were analyzed (AOAC 2000) for

DM (oven method 93015) ash (oven method 94205) CP (Kjeldahl method 98805) fat (diethyl

ether extraction method 200305) and Ca and P (dry ashing acid digestion analysis by

inductively coupled plasma spectroscopy method 98501) Additionally NDF with ash

concentration by the procedure of Van Soest et al (1991) without sodium sulfite or α-amylase

ADF with ash concentration (Robertson and Van Soest 1981) and acid-detergent insoluble lignin

(Goering and Van Soest 1970) were quantified A portion of fecal samples was dried in a forced

air oven at 55degC for 72 h to determine DM and starch content Feeds and feces were gelatinized

with sodium hydroxide for starch concentration analysis by Karkalas (1985) enzymatic method

Feces were collected from the landscape fabric over a 22-h period at the same time of

rumen sampling and 2 h after the last rumen sampling samples were stored at -20degC for later

analysis Particle size distribution of feces and the solid fraction of reticulo-rumen contents was

analyzed via the wet-sieving technique of Maulfair and Heinrichs (2010) using screen sizes 015

0425 060 085 10 118 and 335 mm (VWR Arlington Heights IL) Starters were




66


retained on the top screen assumed to be 47 mm long (square hole diagonal of top screen)

Reticulo-rumen dissection and rumen papillae and wall thickness measurements followed

Lesmeister et al (2004) with 8 papillae measured per sample (40 per area) and rumen wall

thickness was measured twice per sample (10 per area)

Data were analyzed using the MIXED procedure in SAS (Version 94 SAS

Institute Inc Cary NC) as a completely randomized design a completely randomized block

design with trial as block was used when variables from both trials were analyzed together Calf

within treatment was a random effect used to test the fixed effect of treatment trial was a fixed

effect and its interaction with treatment was tested in the model Fixed effect of time and its

interactions with other fixed effects were included in the model when multiple observations

occurred between weeks and within sampling day Repeated measures using autoregressive (1)

covariance structure were used for intake xylose and fecal particle size data Heterogeneous

compound symmetry covariance structure was used for fecal pH and starch goodness of fit

criteria were used to select covariance structures for these variables Packed cell volume () was

used as a covariate for xylose Spatial (power) covariance structure [SP(POW)] was used for

rumen fermentation data because of unequally spaced sampling points Linear and quadratic

contrasts for diets and time after grain feeding between weeks and within sampling day were

tested using the CONTRAST statement Least square means are presented in tables and evidence

for statistical significance was declared at P le 005 with trends at P le 010


In Trial 1 3 calves died for reasons unrelated to dietary treatments before they were

started on experimental diets Ingredient composition of starter (Table 4-1) differed only in the

67

particle size of straw and nutrient composition of PS vs SS MS and LS is similar when straw

chemical analysis is proportionally added to the pellet used to mix those diets The straw put in

the pellet in PS diet did not affect particle size as the Xgm of it and the pellet used for SS MS

and LS was similar The proportion of particles gt 118 mm in PS diet and the pellet used for SS

MS and LS is lower than the recommended particle size (50 of particles gt 119 mm) for calves

fed starter with no forage and without access to consume bedding to insure adequate intake

proper rumen fermentation (Warner et al 1973) prevent physiological abnormalities and initiate

rumination (Porter et al 2007) hence the effect of straw particle size would have been

enhanced Table 4-2 shows BW of calves in each trial which was similar across treatments at

birth and slaughter In all results wk refers to time after starter was available and not

chronological age unless otherwise stated

Mean starter intake was similar across treatments and increased with time by design

(Figure 4-1 Table 4-3) A diet by week interaction was detected in Trial 1 for wk 6 where PS

and MS intake was lower than SS and LS Most of the difference comes from orts of the last

starter feeding before slaughter however it was also influenced by some fistulated calvesrsquo

reduced intake possibly due to acidosis in wk 6 (PS = 2 MS = 2 SS = 1) Starter intake was

greater in Trial 1 when compared to Trial 2 (3559 vs 1928 gwk) Age of calves when starter

was available was greater in Trial 2 (3 wk vs 1 wk) calves in Trial 1 were completely weaned

during wk 6 and the time between trials may have affected the palatability of pellets Milk

replacer pm feeding was withheld in calves not eating at least 50 of their daily starter

allowance the proportion of skipped meals (fixed for uneven animal number) was not evenly

distributed among treatments (total skipped meals 118 PS = 19 SS = 15 MS = 43 LS = 23 )

however it did not affect MR intake across diets possible because the number of skipped meals

was only about 7 of total offered meals

68

Rumen fermentation and digesta particle size

Rumen fermentation data from 12 fistulated calves (3treatment) in Trial 1 is presented in

Table 4-3 Rumen pH decreased linearly with age (Figure 4-1) and the overall value for SS was

lower than that of PS and MS (581 PS 550 SS 575 MS 562 LS P lt 005) This cubic effect

of diet is different from our hypothesis as we expected pH to increase linearly as particle size

increased Possibly intake in wk 6 influenced pH and is responsible for the cubic effect as PS and

MS had higher intakes in wk 6 Beharka et al (1998) observed an increase in rumen pH for larger

particle size when comparing ground vs unground diets Particle size differences in that study

were larger as forage constituted 25 of the starter and grains were also groundunground these

may be reasons why particle size had a greater impact on rumen pH Greenwood et al (1997) also

observed higher rumen pH with diets greater in particle size when forage constituted 15 of

starter The decline in pH with age is consistent with Anderson et al (1987) and Beharka et al

(1998) findings up to 6 wk however they observed a quadratic response to age and calves were

studied for a longer period of time As shown in Figure 4-1 the decline in pH with calfrsquo age is

responsive to solid feed intake increasing with age Figure 4-2 shows pH variation over the 20-h

sampling periods pH dropped after feeding with lowest values recorded at 2 or 4 h post-feeding

after which it gradually increased Anderson et al (1987) observed lowest pH values 1 to 3 h

post-feeding and a faster recovery to pre-feeding values than in the present study at its lowest

value average pH was over 5 which was higher than we observed in this study The pH values

observed by Laarman et al (2012) are also higher than in this study however calves had ad

libitum access to forage and were older Although not specified calves in Anderson et al (1987)

may have also had access to bedding as they were housed in calf hutches At the end of wk 5

cannulated calves (n = 5) showed clinical signs of acidosis anorexia lethargy diarrhea (Owens et

al 1998) and abdominal discomfort Differences in pH were analyzed for calves with acidosis

69

symptoms vs calves not showing these symptoms and it was determined that on wk 5 pH of

calves showing signs of acidosis declined up to 8 h after feeding vs 2 h after feeding for calves

not showing acidosis symptoms (Figure 4-3) As none of the non-fistulated calves in either trial

showed these symptoms at that age it is likely that our attempt to equalize intake by feeding orts

through the cannula created acidosis in these calves The 5 calves showing these symptoms were

often fed through the cannula and the amounts that were fed through the cannula as calves aged

was likely too large and overwhelmed the ability of these calves to maintain pH

Total rumen VFA concentration did not differ by diet but there was a diet by week

interaction where PS had lower concentration than SS and LS in wk 5 and lower than SS in wk 6

As with pH these observations may be related to solid feed intake differences in wk 6 Greater

rumen VFA concentration with smaller particle size was reported by Coverdale et al (2004) and

Beharka et al (1998) although the latter was a numerical difference only (P = 012) In both

studies calves fed smaller particle size rations had increased keratinization of the rumen papillae

which has been shown to reduce the amount of VFA absorption (Hinders and Owen 1965) In the

Greenwood et al (1997) study particle size of diets did not affect VFA concentration Total

concentration of VFA in the rumen increased with age as has been reported by earlier studies

(Greenwood et al 1997 Beharka et al 1998 Coverdale et al 2004) Total rumen VFA

variation over the 20-h sampling periods shown in Figure 4-4 was consistent with previous

reports (Anderson et al 1987 Quigley et al 1992) with peaks between 2 and 4 h after feeding

when pH was at its lowest Molar proportions of individual VFA were not affected by diet

interactions between wk and diet although statistically significant did not seem to follow a

biologically sound trend and thus are not discussed Molar proportion of acetate decreased as

calves aged while proportions of propionate butyrate and valerate increased similar results were

obtained by others (Anderson et al 1987 Beharka et al 1998) however butyrate proportion

decreased at 12 wk of age in the Anderson et al (1987) study Iso-acids molar proportion was low

70

and decreased with calvesrsquo age as was previously reported (Anderson et al 1987 Beharka et al

1998) Rumen NH3 was not different between dietary treatments and decreased as calves aged a

decrease with age is consistent with the literature and is likely a result of increased use by rumen

microbial population (Anderson et al 1987 Beharka et al 1998)

Rumen digesta retained Xgm at slaughter time (12 to 14 h after feeding Table 4-

4) was lower for PS than SS MS and LS this was a result of a lower proportion of particles

retained on the 335-mm sieve for PS than in the 3 other treatments which was compensated by

greater proportions retained on the 3 lower sieves for PS


Particle size starch content and pH of feces measured in Trial 1 are presented in Table 4-

5 Total and retained Xgm of feces were not affected by diet but the proportion of retained

particles on the 335-mm sieve linearly increased (P = 003) as particle size did which was

compensated by a linear decrease (P = 001) in the proportion of particles retained in the 118-mm

sieve as particle size increased Similar fecal Xgm across diets implies that calves were able to

reduce particle size of straw to the same size across diets and this was possibly a consequence of

increased ruminating activity as particle size increased Hodgson (1971) observed calves spent

longer times ruminating with greater diet particle size In adult cattle longer time spent

ruminating increases saliva production and buffers rumen pH (Krause and Oetzel 2006)

however we did not detect an effect of diet on rumen pH in the present study Lack of differences

in fecal particle size contrasts with shorter rumen contents particle size of PS and further supports

the idea that calves had to spend more time or be more efficient at ruminating as particle size

increased Fecal pH was not statistically different between diets however the 2 diets with longest

particle size had numerically higher (P = 013) pH than the other 2 diets Castells et al (2013)

71

observed that calves supplemented with oat hay had lower rectum pH than calves fed

concentrates only or supplemented with alfalfa hay (590 640 and 648 respectively) these

values are not far from those observed in the present study Fecal starch concentration increased

while pH decreased as calves aged (Figure 4-5) starch increase is likely a consequence of an

increased passage rate due to higher intake Other workers have also found a negative correlation

between fecal pH and starch concentration in steers lambs older calves (Wheeler and Noller

1977) and yearling heifers (Depenbusch et al 2008) The decrease in fecal pH is responsive to

greater amounts of starch being fermented in the hindgut (Depenbusch et al 2008) The

proportion of fecesrsquo soluble fraction decreased with age (847 790 727 678 642 599 wk 1

to 6 from the time starter was available) likely a result of less DM coming from MR as starter

intake increased The lack of an age response in retained Xgm in spite of greater proportions of

fecal DM being retained suggests that calves were able to reduce particle size of starter to the

same degree as starter intake increased



Organ weights their proportion of BW and rumen development parameters differ between trials

likely because calves in Trial 1 were older at slaughter and had greater starter intake Particle size

did not affect reticulorumen and abomasum weights in agreement with other reports (Greenwood

et al 1997 Beharka et al 1998) Greenwood et al (1997) suggested that in their study similar

reticulorumen weights were expected because of similar intakes this could also apply to our

study because as in theirs the only treatment difference was particle size of starter and intake was

similar across treatments Xylose absorption was greater for LS vs SS and MS but not SS

72

When the omasum was analyzed as a percentage of BW at harvest it decreased linearly as

particle size increased others have also reported heavier omasums for diets with smaller particle

size (Greenwood et al 1997 Beharka et al 1998) This observation was attributed to an

increased flow of particles with shorter particle size from rumen to omasum (Beharka et al

1998) and to greater muscular development (Greenwood et al 1997) Stevens et al (1960)

described the omasum as a 2-stage pump that transfers digesta from the reticulum to the

abomasum In the first stage the omasal canal vacuums reticulum contents into the canal and

pumps them into the omasal body these 2 contractions are synchronized to primary and

secondary rumen contractions In the second stage the omasal body contracts pumping digesta

into the abomasum or back to the reticulum omasal body contractions do not necessary occur in

synchrony with reticulo-omasal cycles and seem to be initiated by digesta accumulation between

omasal leaves We hypothesize that small feed particles accumulate between omasal leaves when

the particle size of the diet does not provide enough abrasion Accumulation of particles increases

omasum size by distending the omasal body and by greater muscle growth in response to

increased omasal body contractions We observed fully distended omasums with a hard to

remove paste-like matter between omasal leaves in several calves

Rumen development measures of papillae length and width and rumen wall thickness

were not affected by particle size Beharka et al (1998) reported greater length in the dorsal and

blind sacs with greater diet particle size while Greenwood et al (1997) observed papillae length

in the ventral floor of the cranial sac to decrease as particle size increased Conflicting results

between these studies could be related to sampling location In the present study papillae were

measured from 9 locations including all sacs and the interaction between diet and location was

not significant (P gt 01) Fokkink et al (2011) observed longer papillae when a starter greater in

particle size was fed and calves had similar straw intakes however nutrient composition differed

between starters Castells et al (2013) observed that calves supplemented with oat hay had

73

shorter papillae than calves fed concentrates only when keratin layer was similar yet calves had

access to eat bedding Calves in the Beharka et al (1998) study were kept on diets for about 11

wk and fed milk to 8 of BW hence calvesrsquo solid feed intake was likely very high which would

intensify the effects of startersrsquo particle size Also the diet shorter in particle size had 205 of

particles gt 099 mm much less than the recommended 50 of particles gt 119 mm to insure


abnormalities (Porter et al 2007) up to 8 wk of age for calves fed no hay and without access to

consuming bedding materials In the Greenwood et al (1997) study the shorter particle size

starter had 159 of particles gt 17 mm and 508 gt 085 mm which likely did not meet Warner

et al (1977) recommendations either Nevertheless Warner et al (1977) did not measure the

keratin layer in their study for making their suggestions It is clear from these findings that calves

do need a certain amount of large particles for healthy rumen development and papillae growth

yet this requirement is dependent on several factors including diet ingredient composition and

solid feed intake It is possible that in the present study even when particle size of PS diet did not

meet Warner et al (1977) parameters and calves were on experimental diets for the same length

of time and had comparable intakes to Greenwood et al (1997) study that PS particle size met

the abrasiveness requirement for healthy papillae growth and thus increasing straw particle size

had no effect on papillae length and rumen development parameters

Conclusions

Increasing the particle size of starter by changing the particle size of straw at 5

inclusion rate resulted in minimal changes in ruminal fermentation no effect on fecal particle

size pH and starch content and no change in rumen development parameters The size of the

omasum decreased as particle size increased the implications of this change may be beneficial to

74

the calf and need to be elucidated Under the conditions of this study increasing the particle size

of low quality forage to calvesrsquo diets did not improve rumen development parameters or provided

with a more stable rumen fermentation

75

References

Anderson K L T G Nagaraja and J L Morrill 1987 Ruminal metabolic development in

calves weaned conventionally or early J Dairy Sci 701000ndash1005



ASABE 2007 Method of determining and expressing particle size of chopped forage materials

by screening ANSI ASAE S424 1663ndash665






5236





872554ndash2562


Young Calf Iowa State Univ Press Ames Iowa

Depenbusch B E T G Nagaraja J M Sargeant J S Drouillard E R Loe and M E

Corrigan 2008 Influence of processed grains on fecal pH starch concentration and

shedding of Escherichia coli O157 in feedlot cattle J Anim Sci 86632ndash639








Sci 802534ndash2541



76



intake after weaning Animal Sci 1315ndash24







4487



873439ndash3450








933784-3788





Owens F N D S Secrist W J Hill and D R Gill 1998 Acidosis in cattle A review J

Anim Sci 76275ndash286



23395ndash400




Stevens C E A F Sellers and F A Spurrell 1960 Function of the bovine omasum in ingesta

transfer Am J Physiol 198449ndash455

77










Sci 743583ndash3597


no hay Proc Cornell Nutr Conf 116ndash122 Cornell University Ithaca NY





78

Table 4-1 Ingredient and chemical composition and particle size of starters containing 5 straw

differing in particle size either in the pellet (PS) or mixed with the pellet Short (SS) Medium

(MS) and Long (LS)

Item PS Pellet1



Wheat midds 2500 2632


Wheat straw2 500 -

Cane molasses 300 315


Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734

1Pellet used for diets SS MS and LS

2Straw contained ( DM) 39 CP 537 ADF 783 NDF and 828 lignin Geometric mean

particle length was 082 304 710 and 127 mm for PS SS MS and LS respectively

3The premix contained (per kg) 160 g Cu 013 g Co 940 g Fe 014 g I 54 g Mn 004 g Se

670 g Zn 1800 IU vitamin A 600 IU vitamin D 16 IU vitamin E 001 g biotin 293 g


riboflavin 029 g thiamin (Provimi North America Brookville OH)

79



be 47 mm long



be 47 mm long


80

Table 4-2 Description of calves fed starters containing 5 straw differing in particle size either

in the pellet (PS) or mixed with the pellet Short (SS) Medium (MS) and Long (LS)

Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072

1BW of calves at slaughter was heavier in Trial 2 than in Trial 1 (690 vs 613 kg p lt 001)

81

Table 4-3 Intake of calves fed starters containing 5 straw differing in particle size either in the pellet (PS) or mixed with the pellet Short

(SS) Medium (MS) and Long (LS)

P-value

Wk1

Wk

1 2 3 4 5 6 SE Diet Linear Quadratic

Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -

a-cDifferent superscripts indicate diet times week interaction differences (P lt 005)

1From the time starter was fed

2Milk replacer powder intake as fed

3Starter grain with 5 straw as fed

82

Table 4-4 Rumen fermentation of 12 calves fed starters containing 5 straw differing in particle size either in the pellet (PS) or mixed with

the pellet Short (SS) Medium (MS) and Long (LS) in Trial 1

P-value

Wk1

Wk

Diet 1 2 3 4 5 6 SE Diet Dietwk Linear Quadratic

Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84

Table 4-5 Rumen contents particle size of calves fed starters containing 5 straw differing in particle size either in the pellet (PS) or mixed

with the pellet Short (SS) Medium (MS) and Long (LS)

Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219

a-cDifferent superscripts indicate differences (P lt 005) between treatments

1Because of unequal animal numbers SE differ between treatments the highest SE were reported in the table



85

Table 4-6 Starch concentration pH and fecal particle size of calves fed starters containing 5 differing in particle size either in the pellet

(PS) or mixed with the pellet Short (SS) Medium (MS) and Long (LS) in Trial 1

P-value

Diet

Wk

PS SS MS LS SE1

Diet DietWk Linear Quadratic

Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023

1Due to unequal animal numbers SE differ between treatments the highest SE were reported in the table






86

Table 4-7 Digestive system development measurements in calves fed starters containing 5 straw differing in particle size either in the

pellet (PS) or mixed with the pellet Short (SS) Medium (MS) and Long (LS)

P - value

Diet

Diet

PS SS MS LS SE1

Diet Trial DietTrial Linear Quadratic

Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025

Reticulorumen g 721 766 688 742 45

065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099

Organ proportion of BW at harvest

Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069

Papillae length mm 084 079 077 080 006

085 004 084 054 052

Papillae width mm 049 049 048 046 002

057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074


2Rumen wall thickness

87

Figure 4-1 Mean solid feed intake (17 calves ) and rumen pH (12 calves diams) from 1 to 6 wk

after starter was available for calves fed starter containing 5 straw differing in particle size

either in the pellet (PS) or mixed with the pellet Short (SS) Medium (MS) and Long (LS) in

Trial 1

88


wk after starter was available for 12 calves fed starter containing 5 straw differing in particle

size either in the pellet (PS) or mixed with the pellet Short (SS) Medium (MS) and Long (LS) in

Trial 1 Linear effect for wk (P lt 001) cubic effect for time relative to feeding (P lt 001)

89

Figure 4-3 Mean rumen pH variation at -8 -4 0 2 4 8 and 12 h relative to feeding 5 wk after

solid feed was available for 12 calves that showed (5 calves ) or did not show (7 calves )

acidosis symptoms in Trial 1 The probability for the 3-way interaction for acidosis symptoms vs

not week and time from feeding was (P lt 001) Differences between groups at 8 and 12 h after

feeding were significant (P lt 005)

90

Figure 4-4 Mean total VFA variation at -8 -4 0 2 4 8 and 12 h relative to feeding from 1 to 6




91

Figure 4-5 Mean fecal pH () and starch () concentration from 1 to 6 wk after starter was

available for calves fed starter containing 5 straw differing in particle size either in the pellet

(PS) or mixed with the pellet Short (SS) Medium (MS) and Long (LS) Linear effect of wk (P lt

001) for both variables

92

Chapter 5

Summary and conclusions

Two studies were conducted to better understand the effects of increasing starter particle

size on rumen fermentation and rumen development of young calves The particle size of starter

was modified by either changing the particle size of forage in the diet or by reducing the extent of

grain processing In addition the literature was reviewed in regard to the effects of forage on

starter intake as research studies have yielded inconsistent results

A portion of calves in both studies were cannulated before starter was fed which allowed

monitoring rumen fermentation from a very early age The cannula also served for the purpose of

equalizing starter intake in cannulated animals Starter intake was controlled in both studies

because it is the major conditional factor that affects rumen development and rumen fermentation

thus when treatments affect starter intake it becomes a confounding factor for other variables

being measured Orts when present were put through the cannula which allowed having equal

intakes We did observe that this practice negatively affected voluntary starter intake however

Our objectives were to determine treatment differences and therefore it was necessary to equalize

intake Nevertheless the experience from these studies could serve to improve the method for

equalizing intake in future studies Putting orts trough the cannulae once a day only did not

influence starter intake in the first 2 to 3 wk but as the amounts increased with time the load of

fermentable carbohydrates at one time was too large and overwhelmed the rumen buffering

capacity This may have been exacerbated by the lack of feed mastication which would have

produced saliva Addition of a buffering agent mimicking saliva composition was considered

however it would have added another confounding factor Some possible strategies that could

93

minimize the negative impact of putting orts through the cannula on intake and rumen pH are to

do it several times during the day put only a fraction of the orts and do it only for the first 2

weeks These strategies may not equalize intake but may help in reducing intake variability

between calves Feeding orts only for the first 2 wk may help to get the calves started eating solid

feed at an age when variability is most often quite large Limiting the amount of offered starter in

non-cannulated calves did work in these studies and it is recommended for future studies aiming

to have similar starter intake between treatments

An interesting observation in this dissertation is that the dynamics of VFA molar

proportions were different between the two studies Acetate molar proportion increased by week

and by time after feeding in the study where oats particle size was studied while in the study

where straw particle size was evaluated acetate molar proportions decreased by week and did not

increase after feeding Possibly these differences were a response to greater intakes of starters

with higher starch concentration in the oats study which then resulted in lower pH (Figure 5-1)

Particle size between PS treatment in the straw study and diets in the oats study was similar as

was the fiber content between the studies therefore pH differences between studies were due to

intake and starch concentration Rumen pH in the straw study did not reach levels as low as week

4 in the oats study even when at week 6 starter intake was much greater This could be due to an

improved buffering capacity as the calves get older Hence by the time calves in the straw study

reached the intake level of the calves on the oats study at wk 4 the calves in the straw study had a

greater buffering capacity Five of 12 cannulated calves in the straw study showed signs (other

than anorexia and low pH) of acidosis while no calves showed these signs in the oats study

suggesting that the resilience to low pH in young calves is reduced as calves age This could be

related to rumen development because as papillae grow rumen absorption capacity is increased

so more of the endotoxins created by low pH are absorbed

94

In both studies there were not many differences between treatments which is possibly

due to high starch concentration of the diets overshadowing particle size effects Diet starch

concentration and the rate at which starch is fermented in the rumen are possibly the most

influencing factors to rumen development and rumen pH However few reports are found in the

literature that look into starch concentration and its fermentation on rumen development and few

studies report starter starch concentration Moreover few studies report starter particle size even

when investigating forage addition to calf starter Hence the interactions between starter starch

concentration its fermentability and particle size on rumen fermentation and rumen development

warrant further research

It is common to see very different recommendations for the age at which calves need

forage in their diet This is because many factors are going to influence this starter intake is the

one with the greatest impact At the onset of rumen fermentation forage may have a negative

impact on starter intake and hence rumen development but as intake increases forage will be

required to prevent acidosis and hyperkeratinization of rumen papillae The starter intake level at

which forage is needed is dependent on starter nutrient composition and its physical form

Starters with less processed or whole grain may be fed to higher intake levels before forage is

needed when compared to all pelleted starters because the starch fermentation rate is slower

Altogether increasing starter particle size may allow feeding starters without the need of forage

for a longer period of time which could positively affect starter intake and result in faster rumen

development resulting in a smoother transition at weaning

95

Figure 5-1 Mean as-fed starter intake (full line) from 1 to 6 wk after starter was available for

calves in Chapter 3 () and Chapter 4 (Trial 1) Mean rumen pH concentration (dashed line)

for cannulated calves in Chapter 3 () and Chapter 4 ()

VITA


ACADEMIC PROFILE

December 2014 Doctor of Philosophy in Animal Science


August 2011 M S Animal Science


December 2007 B S Animal Science and Agricultural Production

Zamorano University

Valle del Yeguare ndash Honduras

PROFFESIONAL EXPERIENCE

Graduate Research Assistant Department of Animal Science The

Pennsylvania State University

Fruit Production Station Field Instructor Zamorano University Honduras

Research Assistant Department of Dairy and Animal Science The


TEACHING amp SERVICES

Teaching Assistant for 301 Principles of Animal Nutrition course (PSU)

Invited Speaker at Penn State Extension Dairy Cattle Nutrition Workshop

(PSU)

Chaperone and interpreter for the Penn State Dairy Science Club trip to

Costa Rica (PSU)

Teaching Assistant with the 310 Dairy Cattle Production and Management

Lab (PSU)

Invited Speaker at Penn State Dairy Days Cow Camp (PSU)

Invited Speaker at Extension Workshops for Spanish Workers in Dairy

Farms (PSU)

SELECTED PUBLICATIONS

Suarez-Mena F X G I Zanton and A J Heinrichs 2013 Effect of forage particle length on

rumen fermentation sorting and chewing activity of late-lactation and non-lactating dairy

cows Animal 7272-278

Suarez-Mena F X G J Lascano and A J Heinrichs 2013 Chewing activities and particle


with increasing levels of distillers grains J Dairy Sci 965184-5193

Suarez-Mena F X T M Hill A J Heinrichs H G Bateman II J M Aldrich and R L


dairy calf feeds J Dairy Sci 943037-3044

Lascano G J GI Zanton F X Suarez-Mena and A J Heinrichs 2009 Effect of limit

feeding high and low concentrate diets with Saccharomyces cerevisiae on digestibility

and on dairy heifer growth and first-lactation performance J Dairy Sci 925100-5110

The dissertation of Francisco Xavier Suarez-Mena was reviewed and approved by the following

Arlyn J Heinrichs

Professor of Dairy and Animal Science

Dissertation Advisor

Chair of Committee

Kevin D Harvatine

Assistant Professor of Nutritional Physiology

Chad Dechow

Associate Professor of Dairy Cattle Genetics

Robert J Van Saun

Professor of Veterinary Science

Terry D Etherton

Distinguished Professor of Animal Nutrition

Head of the Department of Animal Science

Signatures are on file in the Graduate School

iii

ABSTRACT
























iv


























v










starter intake






health

vi

TABLE OF CONTENTS

List of Figures vii

List of Tables ix

Acknowledgements x


References 3


Introduction 5


Analysis 8

Conclusions 12

References 14


Abstract 17

Introduction 18


Sample analyses 22






Conclusions 35

References 37

Appendix 1 57



Abstract 59

Introduction 60






Conclusions 73

References 75


vii

LIST OF FIGURES


























015) 54














viii















005) 89













() 95

ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














iii

ABSTRACT
























iv


























v










starter intake






health

vi

TABLE OF CONTENTS

List of Figures vii

List of Tables ix

Acknowledgements x


References 3


Introduction 5


Analysis 8

Conclusions 12

References 14


Abstract 17

Introduction 18


Sample analyses 22






Conclusions 35

References 37

Appendix 1 57



Abstract 59

Introduction 60






Conclusions 73

References 75


vii

LIST OF FIGURES


























015) 54














viii















005) 89













() 95

ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














iv


























v










starter intake






health

vi

TABLE OF CONTENTS

List of Figures vii

List of Tables ix

Acknowledgements x


References 3


Introduction 5


Analysis 8

Conclusions 12

References 14


Abstract 17

Introduction 18


Sample analyses 22






Conclusions 35

References 37

Appendix 1 57



Abstract 59

Introduction 60






Conclusions 73

References 75


vii

LIST OF FIGURES


























015) 54














viii















005) 89













() 95

ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














v










starter intake






health

vi

TABLE OF CONTENTS

List of Figures vii

List of Tables ix

Acknowledgements x


References 3


Introduction 5


Analysis 8

Conclusions 12

References 14


Abstract 17

Introduction 18


Sample analyses 22






Conclusions 35

References 37

Appendix 1 57



Abstract 59

Introduction 60






Conclusions 73

References 75


vii

LIST OF FIGURES


























015) 54














viii















005) 89













() 95

ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














vi

TABLE OF CONTENTS

List of Figures vii

List of Tables ix

Acknowledgements x


References 3


Introduction 5


Analysis 8

Conclusions 12

References 14


Abstract 17

Introduction 18


Sample analyses 22






Conclusions 35

References 37

Appendix 1 57



Abstract 59

Introduction 60






Conclusions 73

References 75


vii

LIST OF FIGURES


























015) 54














viii















005) 89













() 95

ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














vii

LIST OF FIGURES


























015) 54














viii















005) 89













() 95

ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














viii















005) 89













() 95

ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














ix

LIST OF TABLES


















Long (LS) 80



Long (LS) 81










x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














x

ACKNOWLEDGEMENTS







invaluable












1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














1

Chapter 1

Introduction





















2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














2

















NRC 2001)






3

References



641215ndash1226



Sci 87E55ndashE65




J 112369-375









Sci 702095ndash2104


DC











Univ Ithaca NY

4



Univ Ithaca NY



5

Chapter 2


Introduction





















6
























7


























8





















Analysis



9


























10


























11


























12













and intake level

Conclusions










13






14

References



641215ndash1226












293



5236






872554ndash2562








Nottingham UK



15






Sci 802534ndash2541


University




Sci 39171ndash179















943547ndash3553






4487



16



873439ndash3450










23395ndash400















Univ Ithaca NY







Sci 801145ndash1156

17

Chapter 3


Abstract




















18





Introduction

















19







rumen epithelium




early age



papillae growth









20






















analysis




21
























Sample analyses












method











23
























24
























25


















cannulated

Rumen fermentation





26


























27

























28


whole oats









et al 2003)















29


























30

























31
























32


























33























34


























35



(1998) studies












greater in wk 2

Conclusions








36





37

References






641215ndash1226







88E9ndashE21








5236





872554ndash2562









38



Sci 802534ndash2541



AOAC Int 9242-49











Sci 911140ndash1149







4487



873439ndash3450









39



933784-3788






DC



21



23395ndash400



75228ndash235














300R1515ndashR1523




40



Scand 5139-44







(Abstr)














Sci 743583ndash3597






967765ndash7776



597






41



42



Item G W



Ground oats1

2500 -

Whole oats1

- 2500




Fat 200 200


Premix2

075 075

Salt 060 060





DM 8807 8766

CP 1895 1839

Starch 4260 4360

Crude fat 491 483

ADF 779 705

NDF 1230 1314

Ash 528 573

Ca 080 077

P 053 057

Particle size mm

Xgm retained

3 123 184

Sgm retained

3 115 118

Xgm total

4 058 091

Sgm total

4 156 172

particles gt 118 mm

5 4100 6578






43



be 47 mm long



be 47 mm long


44



Diet P-value

G W SE

Calves n

Trial 1 4 4 -

-

Trial 2 4 5 -

-

Trial 3 3 4 -

-


058


057

45


P-value

1Wk

Wk


Calves n G 8 - 8 - 8 - 4 -

W 9 - 9 - 9 - 5 -

Rumen pH G 626 014 557 014 553 013 491 018

085 041 lt001 090

W 605 013 566 013 543 013 501 016

Rumen NH3 mgdL G 568 090 518 088 587 088 468 106

026 002 002 014

W 588 085 378 083 287 083 386 098

Total VFA mM G 6374 861 10750 850 9996 860 7677 965

031 007 lt001 lt001

W 4963 813 8408 803 9057 811 7771 897


Acetate G 6278 230 6239 226 6794 225 7685 270

080 008 lt001 lt001

W 6050 218 6696 214 6760 213 7770 250

Propionate G 2042 178 2345 174 2384 173 1802 211

095 012 lt001 lt001

W 2313 168 2251 165 2166 164 1791 195

Butyrate G 1428 175 1190 174 556 174 312 192

064 lt001 lt001 046

W 1249 165 818 165 793 165 199 180

Valerate G 097 019 152 019 174 019 135 023

068 005 012 lt001

W 145 018 134 018 188 018 127 021

Isovalerate G 081 011 053 011 056 011 064 014

050 lt001 lt001 lt001

W 133 011 058 010 055 010 044 013

Isobutyrate G 063 008 037 008 035 008 031 010

086 033 lt001 lt001

W 077 008 037 008 034 008 026 009


46


Diet P-value

G SE W SE

Calves n 11 - 13 -

Xgm retained1 104 010 190 009

lt001

Sgm retained1 115 001 121 001

lt001

Retained DM

335-mm sieve 908 239 3966 219

lt001

118-mm sieve 1519 116 1535 107

092

1-mm sieve 770 041 467 038

lt001

085-mm sieve 616 027 380 024

lt001

06-mm sieve 1765 089 1023 081

lt001

0425-mm sieve 1706 071 977 065

lt001

015-mm sieve 2716 267 1651 245 001



47


pellet (W)

P-value

Wk1

Wk


Calves n G 11 - 11 - 11 - 7 -

W 13 - 13 - 13 - 9 -

Xylose mgdL G 3665 212 2769 212 3416 212 3398 254 076 lt001 020 029

W 3475 194 3572 194 3367 194 3099 228

Xgm retained2 G 084 007 074 007 082 007 081 009

lt001 083 037 017

W 117 007 108 007 120 007 126 008

Sgm retained2 G 115 001 112 001 113 001 112 001

lt001 084 008 095

W 123 001 121 001 123 001 120 001

Xgm total3 G 038 002 038 002 041 002 042 002

lt001 017 lt001 039

W 042 002 044 002 049 002 054 002

Sgm total3 G 140 003 137 003 140 003 140 003

lt001 024 003 044

W 151 003 151 003 158 003 160 003

Retain

335-mm sieve G 610 261 312 261 494 261 343 329

lt001 046 056 032

W 2116 240 1632 240 2339 240 2407 294

118-mm sieve G 1116 106 874 106 991 106 1041 136

010 022 061 059

W 1137 098 1272 098 1111 098 1111 121

1-mm sieve G 565 051 638 051 612 051 548 066

004 094 096 009

W 469 046 530 046 552 046 493 059

085-mm sieve G 458 029 391 029 458 029 575 038

lt001 001 026 004

W 378 027 341 027 352 027 312 034

06-mm sieve G 1748 078 1690 078 1859 078 1947 096

lt001 004 013 084

W 1216 071 1368 071 1260 071 1227 085

48

0425-mm sieve G 1901 101 2022 101 2145 101 2227 129

lt001 050 005 035

W 1385 093 1543 093 1518 093 1454 115

015-mm sieve G 3602 189 4073 189 3443 189 3319 235

001 047 002 032

W 3298 173 3314 173 2868 173 2996 210

Solubles of DM4 G 8276 241 7289 241 6641 241 6226 301

081 069 lt001 005

W 8422 221 7560 221 6442 221 6226 269







49



Diet P-value

G SE W SE

Calves n 11 - 13 -


Carcass kg 453 10 444 09

052


006

Omasum g 126 9 126 8

097


001

Liver g 1194 45 1236 41

050

Spleen g 165 297 178 240

097

Organ weight BW


015

Omasum 021 001 021 001

076

Abomasum 040 001 046 001

lt 001

Liver 199 006 209 005

021

Spleen 028 001 030 001

009

Rumen


009


011


033


068


069

Small intestine


023

Crypt depth mm 027 001 024 001 008


arborized


50






51






52




53




feeding (P lt 001)

54






55




lt 001)

56






57

Appendix 1



A

B

58



A

B

59

Chapter 4


rumen fermentation

Abstract



















60







Introduction
















61


























62








fermentation
















63


























64

















particle length









65

























66
























67

























68

























69


























70
























71























72


























73



















Conclusions





74




75

References












5236





872554ndash2562













Sci 802534ndash2541



76










4487



873439ndash3450








933784-3788









23395ndash400






77










Sci 743583ndash3597







78



(MS) and Long (LS)

Item PS Pellet1





Wheat straw2 500 -



Premix3 075 079

Salt 075 080




DM 8804 8644

CP 1769 1998

Starch 3706 3950

Crude fat 379 373

ADF 839 657

NDF 1522 1243

Ash 613 617

Ca 090 106

P 055 057

Particle size

Xgm retained

4 119 119

Sgm retained

4 117 116

Xgm total

5 061 060

Sgm total

5 153 154

gt 118 mm

6 3606 3734








79



be 47 mm long



be 47 mm long


80



Diet P-value

PS SS MS LS SE

Calves n

Trial 1 4 4 4 5 -

-

Trial 2 7 6 6 6 -

-

BW at birth kg 435 434 445 439 12

093

BW at slaughter kg1

647 652 634 672 25

072


81



P-value

Wk1

Wk


Trial 1

MRI gwk2 4813 4813 4813 4813 2301 0 77

086 lt 001 lt 001

Starter intake gwk3

PS 344 825 1647 2957 6410 7533a

748

044 lt 001 lt 001

SS 419 991 1812 2808 5533 11373b

748

- - -

MS 405 1005 1776 2844 5021 8202a

748

- - -

LS 405 1005 1820 2800 5366 12104b

669

- - -

Trial 2

MRI gwk2 4761 4706 4348 3683 2381 1957 114

056 lt 001 lt 001

Starter intake gwk3

PS 310 895 1598 2158 3375 4031 319

069 lt 001 004

SS 322 962 1640 2157 3195 3703 344

- - -

MS 152 533 1206 1727 2634 3588 344

- - -

LS 291 754 1399 2276 3600 3759 344 - - -





82



P-value

Wk1

Wk


Rumen ph PS

654

596 573 579 550 536 012

004 008 lt001 006

SS

562

581 570 557 525 503 015

MS

610

610 570 593 544 520 012

LS

591

589 566 571 543 511 012

NH3 PS 285 183 414 260 293 201 047

011 lt001 lt001 lt001

SS 352 626 435 288 248 201 053

MS 257 380 202 307 380 117 045

LS 341 279 234 239 194 116 045

Total VFA mM PS 4065 6534 8323 8229 5916 11506 1238

054 lt001 lt001 061

SS 3132 6533 9079 9364 10547 15968 1309

MS 4838 6868 8770 8249 8089 12631 1229

LS 4498 7042 10138 10190 11357 14887 1229


Acetate PS 6385 6591 6531 5731 5219 5276 317

095 lt001 lt001 lt001

SS 7435 7368 6801 5897 5085 4381 346

MS 6400 6554 6958 6226 5040 4857 314

LS 6882 6914 6520 5904 4975 4759 314

Propionate PS 2181 2338 2579 3535 3273 2789 207

072 lt001 lt001 018

SS 1604 2258 2444 3037 3022 2924 231

MS 2439 2184 2166 2692 2987 2941 204

LS 2175 2345 2282 2724 3013 3702 204

Butyrate PS 1052 874 604 451 775 1394 229

093 lt001 lt001 lt001

SS 644 142 532 724 1253 1640 248

83

MS 842 936 667 728 1254 1517 227

LS 708 502 898 959 1277 919 227

Valerate PS 162 113 205 191 585 482 082

092 lt001 lt001 lt001

SS 084 003 137 273 569 1006 093

MS 149 214 147 233 595 634 081

LS 076 159 231 307 644 572 081

Isovalerate PS 136 045 049 057 110 033 011

033 lt001 lt001 lt001

SS 151 039 050 044 047 018 013

MS 105 067 037 072 087 028 010

LS 099 048 042 063 059 026 010

Isobutyrate PS 098 039 031 034 038 025 010

073 007 lt001 lt001

SS 081 030 036 025 023 016 012

MS 064 045 025 048 038 023 010

LS 061 032 026 043 031 021 010


84



Diet

PS SS MS LS SE1

Xgm retained2 086

a 120

b 131

b 119

b 009

Sgm retained2 114

a 120

b 122

bc 124

c 001

Retain DM

335-mm sieve 357a

1766b

2471b

2410b

358

118-mm sieve 1425 1638 1306 1019 208

100-mm sieve 614 562 565 486 061

085-mm sieve 527 456 424 350 062

060-mm sieve 1816a

1458b

1321b

1337b

071

0425-mm sieve 2098a

1671b

1544b

1612b

098

015-mm sieve 3164a

2449b

2369b

2785ab

219





85



P-value

Diet

Wk

PS SS MS LS SE1


Starch 183 255 182 167 039

042 086 lt 001 lt 001

pH 630 631 659 658 011

013 041 lt 001 lt 001

Xgm retained2 066 069 068 064 003

040 055 035 001

Sgm retained2 111 114 114 112 001

004 080 013 004

Xgm total3 036 037 037 035 001

045 012 001 lt 001

Sgm total3 133 135 135 132 001

023 035 020 lt 001

Retain DM

335-mm sieve 300 562 662 502 070

001 089 028 041

118-mm sieve 629 692 525 437 064

004 033 050 lt 001

100-mm sieve 428 410 411 374 036

070 018 001 001

085-mm sieve 311 298 305 245 026

023 095 003 010

060-mm sieve 1423 1282 1247 1214 109

053 013 lt 001 007

0425-mm sieve 2107 1940 1913 2021 074

026 097 001 052

015-mm sieve 4798 4816 4937 5207 279

066 063 003 001

Solubles of DM4 7020 7272 7150 7107 222 088 050 lt 001 023







86



P - value

Diet

Diet

PS SS MS LS SE1


Xylose mgdL 338 305 305 350 14

002 lt 001 073 051 lt 001

Slaughter data

Carcass kg 479 472 464 494 16

057 008 044 059 025


065 lt 001 088 093 092

Omasum g 245 217 206 200 17

027 lt 001 097 006 052

Abomasum g 265 292 264 265 11

025 lt 001 098 058 024

Liver g 1135 1146 1083 1107 43

073 lt 001 095 044 088

Spleen g 167 177 159 170 10

063 001 070 083 099


Reticulorumen 110 117 106 109 005

055 lt 001 074 054 065

Omasum 038

033

032 029 002

006 lt 001 062 001 067

Abomasum 041 045 042 039 002

020 003 069 040 006

Liver 176 175 171 164 005

029 lt 001 039 008 047

Spleen 026 027 025 025 001

050 019 035 046 069


085 004 084 054 052


057 lt 001 059 022 054

RWT mm2 079 079 080 076 007

097 lt 001 090 080 074



87




Trial 1

88





89






90





91





92

Chapter 5






















93

























94





















95




VITA


ACADEMIC PROFILE






Zamorano University











(PSU)


Costa Rica (PSU)


Lab (PSU)



Farms (PSU)














particle size of calf starter: effects on digestive …

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