RELATING FORAGE COMPONENTS TO FORAGE

QUALITY

Shelby Filley, Douglas County

David Bohnert, EOARC, Harney County

Oregon State University Extension Service, Department of Animal Sciences

Quality Forage - What is it ?

“contains a high level of digestible energy and is consumed in large amounts per unit time”

Kim Cassel, former University of Maryland dairy nutritionist

Quality Forage - What is it ?

“must be high in intake, digestibility, and efficiency of utilization”

Dale Waldo, USDA nutritionist

Importance of Forage Quality

Accurate Prediction of Livestock production

Forage Marketing

The Nutrition Puzzle

PROTEIN FAT

ASHORMINERALS

SUGARS & STARCHES

WATER

FIBER

D

RY

MATTER

MAINTENANCE

GROWTH

PREGNANCY &REPRODUCTION

PRODUCTION

COMPONENETSOF FEED

ANIMALREQUIREMENTS

Plant Cell

•PROTEIN•SUGARS•STARCH•PECTINS•FATS

PRIMARYWALL

SECONDARYWALL

CELL CONTENTS

CROSS SECTION

Inside

SECONDARY WALL

PRIMARY WALL

CELLULOSE

HEMICELLULOSE

LIGNIN ACIDDETERGENTFIBER (ADF)

NEUTRALDETERGENTFIBER (NDF)

OUTSIDE

Forage ADF and Dry Matter Digestibility

57

59

61

63

65

67

69

28 29 30 31 32 33 34 35

Forage ADF (%)

Dry

Mat

ter

Dig

esti

bili

ty (

%)

Adapted from Miller et al. (1991)

Derived Terms

DDM - digestible DM 88.9 - (.779 X ADF%)

TDN - total digestible nutrients 88.9 - (.79 X ADF%)

Derived Terms, cont’d

NEm - net energy for maintenance; Mcal/lb (TDN% X .01318) - .132

NEg - net energy for growth; Mcal/lb (TDN% X .01318) - .459

NEl - net energy for lactation; Mcal/lb (TDN% X .01114) - .054

Inside

SECONDARY WALL

PRIMARY WALL

CELLULOSE

HEMICELLULOSE

LIGNIN ACIDDETERGENTFIBER (ADF)

NEUTRALDETERGENTFIBER (NDF)

OUTSIDE

Forage NDF and Dry Matter Intake

.0

.5

1.0

1.5

2.0

2.5

3.0

3.5

38 42 46 50 54 58 62 66 70 74 78

Forage NDF (%)

Dry

Mat

ter

inta

ke (

% o

f B

W)

Adapted from Mertens (1985) & Burns et al. (1997)

DMI - dry matter intake 120 / NDF%

RFV - relative feed value (DDM X DMI) / 1.29

CP - crude protein N% X 6.25

Derived Terms, cont’d

Forage Quality and Animal Performance

Chemical Composition(CP, NDF, ADF, Vit., & Minerals)

Digestibility

Palatability

Rate of Passage

Availability

ForageNutritiveValue

ForageConsumed

AnimalPerformance

Proper sampling

Analysis Results

COMPONENTAS

SAMPLEDDRY

MATTERBASIS

% MOISTURE 9 *****

% DRYMATTER

91 *****

Analysis Results

COMPONENTAS

SAMPLEDDRY

MATTERBASIS

% CRUDEPROTEIN

18.6 20.4

% ADJUSTEDCRUDEPROTEIN

18.6 20.4

Analysis Results

COMPONENTAS

SAMPLEDDRY MATTER

BASIS

% ACIDDETERGENTFIBER (ADF)

30.6 33.6

% NEUTRALDETERGENTFIBER (NDF)

37.0 40.7

% NON-STRUCTURALCARBOHYDRATES(NSC)

24.5 26.9

Analysis Results

COMPONENTAS

SAMPLEDDRY MATTER

BASIS

% TOTALDIGESTIBLENUTRIENTS(TDN)

55 60

TYPICAL CHEMICAL COMPOSITION OF GRASSES

MATURITY CP ADF NDF

VEG-BOOT >18 <33 <55

BOOT-EARLY HEAD 13-18 34-38 55-60

HEAD-MILK 8-12 39-41 61-65

DOUGH <8 >41 >65

TYPICAL CHEMICAL COMPOSITION OF ALFALFA

MATURITY CP ADF NDF

Bud-First Flower >19 <31 <40

F.F.- mid bloom 17-19 31-35 40-46

Mid-full bloom 13-16 36-41 46-51

Post bloom <13 >41 >51

Forage Marketing

Moore (1978) suggested producers will invest in high quality forage if: Forage is a large part of the diet Animal productivity increases as forage

quality increases Increased animal productivity is

profitable

Forage Monetary Value

The monetary value of a

forage must reflect its

intended use in a feeding

program !

Influence of Alfalfa Quality on Milk Production

50

55

60

65

70

95 117 136 148

Relative feed Value (RFV)

Milk

pro

duct

ion

(lb/d

)

Adapted from Turnbull et al. (1982)

Influence of Alfalfa Quality on ADG of Beef Steers

1.0

1.5

2.0

2.5

3.0

128 137 167

Relative feed Value (RFV)

ADG

(lb/

d)

Adapted from Miller et al. (1991)

WHY DO I NEED THIS INFORMATION ??

FORAGE

COMPONENETS

&

QUALITY

ANIMAL

REQUIR

EMENTS

THE NUTRITION PUZZLE

Thank-you

Forage Quality Determinants

Total Nitrogen

ADF

NDF

Measured

Crude Protein

TDN

Digestible DM

Dry matter intake

Derived

Other Terms

NET ENERGY (MCAL/LB)NE lactation

NE maintenance

NE growth

DIGESTIBLE ENERGY (DE) (MCAL/LB)

TDN (%) for HORSES

Measured Terms

DM - dry matter

Total N - nitrogen content

DIN - rumen degradable intake nitrogen

UIN - rumen undegradable intake nitrogen

Measured Terms

NDF - neutral detergent fiber

ADF - acid detergent fiber

ADFN - acid detergent fiber N

Derived Terms

CP - crude protein N% X 6.25

DIP - degradable intake protein

DIN% X 6.25

UIP - undegradable intake protein

UIN% X 6.25

ADFCP - ADF CP

ADFN% X 6.25

Derived Terms

ACP - available CP (CP% X [100 - {ADFCP% -12%}]) / 100

DCP - digestible CP CP% X .72

DDM - digestible DM 88.9 - (.779 X ADF%)

TDN - total digestible nutrients 88.9 - (.79 X ADF%)

GRASS/CLOVER HAYAND HALAGE

LOW-PROTEIN

(5-8.9%CP)

MID-PROTEIN

(9-11.9%CP)

HIGH-PROTEIN

(12-16%CP)

HAYLAGE(1 SAMPLE)

CRUDEPROTEIN (%) 6.9 9.9 12.5 9.0ACIDDETERGENTFIBER (%) 42 39 37 44.1NEUTRALDETERGENTFIBER (%) 66 64 57 65.8TOTALDIGESTIBLENUTRIENTS(%) 56 58 60 57

% OF SAMPLES 64 28 8 -

ALFALFA BASED FORAGESALFALFA/

GRASS MIXALFALFA ALFALFA

HAYLAGE

CRUDEPROTEIN(%) 17 - 20 16- 20 20ACIDDETERGENTFIBER (%) 31 -38 34-43 41

NEUTRALDETERGENTFIBER (%) 43 - 50 41-53 50TOTALDIGESTIBLENUTRIENTS(%)

59 - 61 56-60 57