UNIVERSITI PUTRA MALAYSIA

EMBRYONIC DEATHS IN THE SAHIWAL FRIESIAN COWS IN AN INSTITUTIONAL FARM

IN MALAYSIA

ROSLAINI BT. HJ. RUSLI

FPV 1998 3

EMBRYONIC DEATHS IN THE SAHIW AL FRIESIAN COWS IN AN INSTITUTIONAL FARM

IN MALAYSIA

by

DEDICATION

I dedicate this thesis to my dear husband, Dr. Abdul Latif bin Borhan and

daughters, Laila Syahira, Nurul Ilani, Maya Sofia and Salma Athira who has been

my inspiration throughout the whole course of the study.

ii

ACKNOWLEDGEMENTS

I am immensely grate ful to Dr. Abd. Wahid bin Haron for his guidance

t hrou ghout my study at Universiti Putra M alaysia and for his invaluable comments and

su ggestions in the preparation of the thesis. His willin gness to be the Chairman of the

Supervisory committee and keen interest in my research projects are hi gh ly

appreciated. My appreciation is also extended to Pro f. Emeritus Dr. M.R. Jainudeen

and Dr. Nadzri bin Salim, committee members , for their constructive ideas and

su ggestions durin g the thesis preparation

I also would like to express my gratitude to the Director General of Veterinary

Services for allowin g me to pursue the study at the university and usin g the farm

facilities to ca rry out the expe riments , to Dr Abas Mazni of Mardi for the supp ly of

I VF frozen embryo , and to the Director of National Institute of Biotechnolo gy for the

use of its mobile ET vehicle and equipment durin g embryo recovery.

Appreciation is due to Mr. Choo Teck Wah and sta ff of Pusat Te makan

Haiwan Air Hitam, Kluan g for their assistance and care of the experimenta l animals;

and friends and col le gues, Dr. Rosnina Yuso £I: Dr. Un gku Chula n and Dr. Rahim

Mutalib of UPM , Dr. Kamal Hizat of Mardi, Mr. Yap Ken g Chee , En. Abu Bakar

Daha ri of the Clinic al Depa rtment , En. lsa Sit am (PTHAH), En. Ram li Ko rnin g (NIB)

and Dr. Falizah Abdullah and Dr. Siti Romlah Md. Jais who has contribute d in the

course of study and preparation of the thesis.

iii

TABLE OF CONTENTS

Page DEDICATIONS.. . . ...... . . ..... . . .. . .. . . . ... . . .. . ..... . . . . .. . . ....... . . .... . . . . . . . . . . . . . . ... 11 ACKNOWLEDGE MENTS.. . . . . ... . . . . .... . . . . . . . .. . . . . . . . . . . . . . . . . ... . . .. . . . . . . .. . . . . iii LIST OF T ABLES.... . . ... . . ......... ...... ...... ......... .......... ... ...... .............. VlI LIST OF FIGU RES .... . . . .. . . . ..... . . . . .... . . ...... . . . . . . ... . . .. .. . ... . . ..... . . . ... . . . . . . . . viii LIST OF PLATES.. ... . . .... . . . . ... ......... . . ... . .. . . . . . .. .... . . . . . . . .. . . . . . . . . . . . . . . . . . . . . IX ABST RACT..... ... . . . . .. . ....... . . .. . .... ..... . . . . . . . . . . . .. . . . . . . . . . . . . . ... . . . . . . . ... . . . . . . . .. X ABST RAK .... ........ ...... ...... ......... ...... ..... .... ..... .......... .... ..... ....... .... ... XII

CH APTER

I I NTRODUCTION . . . . . . . ....... . . ... . . . . .. ....... . . . . . . .... . . . ..... . .... . . .. . . . . . 1

II LITERATU RE REVIEW

The Reproductive Pe rfo rmance in the Sahiwa l Friesian Cows in the Tropics ... . . . . ... . . . . ... . . . . . . . . . . . . . . . . . ..... . . . . . . . . . . 4

Conception Rate . . . . . . . .. . . . .. .... . . . .. . . . . . . . . . . . . . . . . . . . .... . . . . . . . . . . . 4 Cal vin g Interval . . . ... . . . . . . . . ..... . . .. . . . . . . . . .. . . .. . . . ... ............... 5 Reproductive E fficiency . . ...... .. . . . . . . . . . . . . . ... . . . . ... . . . . . .. . . . . . . 5

Factors In fluencin g Reproductive Performance . . ... . ..... .......... . . 6 Factors Affectin g the Acyclic Periods . . . . . . .. ...... . . . . . . . . . .. 7 Factors Contributin g to Conception Failure ..... . . . . . . . . .. . . 9

Methods of Determinin g Embryonic Mortality . . ... . . ..... . . . . . . . . .. . 13 Breedin g Records .. .... . . ...... . . . . . . . ... . . . .. ....... . . . .... . . . ........ 13 Monitorin g post Breedin g Pro gesterone Profi les .. . . . . . .. 14 Breedin g and S lau ghter Experiments .. . . . . . . .................. 14 Recovery of Ear ly Embryos . . . . . . . ..... . .. . . . . . ... ...... . . . . . . . .. 15

Methods of Assessin g Emb ryo Viabi lity . . . . . . . .... . . . ... ...... . . . . . . . . . 15

Early Pre gnancy Factor (EP F) . . . . . . ...... . . . . . . . ........ .. . . . .. 15 Pro gesterone Radioimmunoassay (RIA) Procedure . . . . . .... . . . . . . . . . . . .... . . . . . . . . . . .. . . . . . . . . . . ... . . .... . . . . . .. .. 1 7

The Emb ryo Transfer Technique .. . . . . .. . .... . . .......... . . ....... . . . . ... 17 Superovu lation Treatment . . . .. .. . . . . . . . . . . .. . .. . . . .............. 1 7 Synchronisation of Oestrus .. . . . . . . . ... . . . . . .. . . . . .. ... .. . . .... . . 18 Emb ryo Recove ry, Eva luation and Transfer ...... . . . . . . . 20

Conclusion . . . . . . . . . ....... ... . . . . . . . . . . .. ... .. . . . ... .... . . . .. . . . . .... . ........ ..... 23

ill MATE RIALS AND METHODS

Fa rm Histo ry .... . . ..... ...... . . . . . . . ..... . . .. ... .. . . . . . .. . . . . ... . . . . . . .... . . . . . . . . . 24 Location of the Study. . . . . . ....... .. . . . . . . ... . ... . . . . . ........ . . . . . . 24 Farm Mana gement Practices...... ... . . ..... ... . . . ............... 25 Breedin g Mana gement. . . . .. ..... . . . . . . . . .. ... . . . . .. ............ . . . . . 25

i v

CHAPTER Page

Embryo Transfer.... . . . . .. . .. .... . .. . . ..... . .. . . . . . .. . . . . . . ...... . .. . . . .. . .. . . . . . . 26 Induction of Oestrus. . ..... . . .. ........ .......... ................ . . 26 Induction of Multiple Ovulation... ... . . . . ...... . ........... . . . . 26 Recovery of Embryos. . . . . . . . . . . . . ...... . . .... . ................ ..... 27 Embryo Search and Evaluation. . . . . . . .... . . . . . . . . . . . .. . ........ 29 Non surgical Transfer of Seven Days Old Embryo. . .. . . . .. . . .......... . ....... .. . . ......... ....... ...... . . ....... . . .. 30

Blood Sampling .. . ............... . .................... .......... . .. . .. . ... . ...... 31 The Progesterone Radioimmunoassay Procedure (RIA)................................................................................... 31

Progesterone Assay. . .................. ................. ...... ........ 32 Assay Calculation. . . . . .. . .. . .... . . ... . . . . . ..... . . ... . . . . ... . . . . ... . . .. . 32 Validation of the Radioimmunoassay. . . .. . . . . . . . .. . . . . .... . . . . 33 Interpretation of Progesterone Profiles.. . . . . ......... . . . . .. . . 34

The Rosette Inhibition Test ................................................... 35 Procedure for Lymphocyte Separation.... ........ ............. 36 Antilymphocyte Serum Preparation. . . . .. . .. . .. ... . . . . .. . . . . . . . . 37 Guinea Pig Serum ....................................................... 38 Sheep Erythrocyte Suspension........... . . .... . ...... . ..... . . . . . . .. 38 Test Procedure for Rosette Inhibition Test..... . . .. . . . . .. .. . . 38 Validation of the Rosette Inhibition Test........ . . . . . . . . . . ... . . 41 Interpretation of Results. . ... . .... . .. ... ..... . . . . . . ... ... . . . ... . . . .... . 42

IV THE FERTILISATION RATE AND PATTERNS OF EMBRYONIC DEATH IN THE SAHlWAL FRIESIAN COWS

Introduction .... . . .............. . ...... . . . .............. .. . . . .. . ........ . . . . .... . . . . . .. . Materials And Methods ... . ........ . .... . . .......... . . ... . ....... . . . ....... . . . . . . .

Breeding Management. ... . ..... ....................... .... ............ . Embryo recovery .. .... . . . ........ .......... . . . .... . .. ... . . . ..... .... . . . . . . Progesterone Profiles .. . . ... . .. . . ... ........ . . ... . . .. .......... . . .. . .. .. . Serum Sampling . . ........... ..... ... . . . . .. ....... . . ... . . . ....... . . . . . . . . . . Estimating Fertilisation Rate and Viability Rate .... . . . . . . . .. . . . .... . . . . . .. . ... . . ... . . . ... . ...... ... . . . ..... . . . Estimating Embryonic Mortality ... .... . . . . . . . ..... . . . . . . ....... . .

Results ...... . .. . . . . . .. . ... . . ... . .. . .. . . ..... . . .... ... . . . . . .. . . .. . . . . . . . ......... . . . ...... . Reproductive Efficiency .. .... . . .. . . . . . . . . . .... . . . . . ... . ... . . . . . ....... . Fertilisation and Viability Rate . ...... . . .. ... .. .......... . . ........ .. The Stage and Rate of Late Embryonic Mortality ... . .. . .. . . Patterns of Embryonic Mortality ..... ................. . ... ... . ..... .

Discussion .. ...... ...... . .... .... ......... .... . .. . ........ . . . . .. . ........ .. .. ...... . . . . . Limitation of the Study . . . ... . . . ......... ..... . . .. .. . . ...... ........... . E t· t' F rt'I' t' R t sima Ing elisa Ion a e .. . . . . . . . ...... . . . .. ... .. ..... . . ..... . . . .

v

44 45 45 45 46 46

46 46 47 47 48 51 52 53 53 54

CHAPTER Pa ge

Emb ryonic mo rtality . . ........................ ..... ..... ...... ... ........ 55 Patterns of Embryonic Mor tality .. . . . . . . . ......... . . . . . .. ... . ... . . 57 Reproductive Pe rfo rmance............. . . . . ......... . . . . . ................ 58

Conclusion . . . . .. ..... ..... ........... ....... ................. ...... .......... .... ...... .... 57

V EFFECTS OF ST ALL FEEDI NG AND CIDR TREAT MENT ON T HE PREGN ANCY RATE

Introduction . . . ..... .... .. . . . ... . . . . ............................. ... . . ............ ... . . . . 60 Materials And Methods ........................................................... 61

Selection of Expe rimental Animals.... ............... .............. 61 Oestrus Synchronisation .. . .............. . . .. . . ........... ...... . ... . . . 62 Mana gement of Experimental Animals .......................... 62 Transfer of Emb ryos ..................................................... 62 Serum Samplin g. . .... . . . . . . ... ....... . . . . . ...... .......... .... .. . .. . . ...... 63 Serum Sample Analysis and Interpretation........ . ............ . 63 Conception Rate of Heifers Under Natural Breedin g...... .................. ........ ......... . . ............... 63 Statistical Analysis ....................................................... 64

Results ... . . ....... . ... . . . .. . ............................................................. 64

Pro gesterone Profiles of Heifers .................................. 64 Conception Rate of Heifers to Natural Breedin g............ 65 Serum Pro gesterone Profiles of Treatmen t Groups.. ...... 65 Pre gnancy Rate of Treatmen t Groups.. ....... ... . . . ............. 65 Effect of Stallfeedin g on the Pre gnancy Rate.... . . . . . . .... . . 67 Effect of CIDR Treatmen t on Pre gnancy Rate................ 67

Discussion ............. . . . . . ................... ............................. . ..... . ...... 68 Conclusion . . . . . . .......... . . . .... . . ........ . . ................ . ........ . ............... . . 73

VI GENERAL DISCUSSION . . . . ..................... .................. .......... 74

VII S UMMARY AND CONCLUS ION ... ...................... . .............. 76

REFERENCES .. . . . . . . . .. . . . . . . . . . . . . .... . . .. .. . . . . ......... . .... . . .. . ....... . ... . .... . ...... . . . 78

APPENDICES ... . . . . .. .... ............... .......................................... ............. 90

B IOGR AP HICAL SKETCH . . ...................... . .................. ...... .............. 97

vi

Table

1

2

3

4

5

6

7

8

9

10

11

12

LIST OF TABLES

Serum Progesterone Profiles of Inseminated Cows (N=50) ................................................................... .

Embryo Recovery in Sahiwal Friesian Cows on Day 7 Post Artificial Insemination ............................... .

Embryonic Loss as Determined by Serum Progesterone Profile of Sahiwal Friesian Cows Beyond Day 25 Post AI ........................................... .

Embryonic Death Between Fertilisation and Day 60 of Pregnancy in the Sahiwal Friesian Cows. Data Extrapolated From Table 2 and 3 ................... .

Reproductive Status of Sahiwal Friesian Heifers ............... .

Estimated Pregnancy Rate of Sahiwal Friesian Heifers Under Natural Service .......................................... .

No. of Recipient Heifers with Conceptus Based on EPF Under Different Treatment .................................................. .

Association of Treatment Exposure and Embryonic Loss .................................................................................. .

Nutrient Composition of Palm Kernel Cake (PKC) (Solvent Extracted) .............................................................. .

Nutrient Composition of B. decumbens (At three weeks) .................................................................... .

Analysis of Variance of Serum Progesterone Levels Between Group I and Group III Recipients ........................... ..

Analysis of Variance of Serum Progesterone Levels Between Group I and Group II Recipients .............................. .

vii

Page

47

51

52

53

63

63

66

68

91

91

92

93

LIST OF FIGURES

Figure Page

1 Principle of the Rosette Inhibition Test .................. 35

2 Schematic Presentation of the Rosette Inhibition Test . . . . . . . .. . . . . . ......... . . . . . . . .. . .. . . . . ......... . . . . ... 39

3 Post Insemination Progesterone Profiles Indicative of Ovarian Status in Sahiwal Friesian Cows: Anovulatory, Short Cycle, Late Embryonic Death, Pregnant and Luteal Phase Insemination ................................................ 48

4 Progesterone Profiles and Embryo Viability of Group I Recipients As Determined by the Rosette Inhibition Test Post Embryo Transfer ......................... 94

5 Progesterone Profiles and Embryo Viability of Group II Recipients as Determined by the Rosette Inhibition Test Post Embryo Transfer ....................... 95

6 Progesterone Profiles and Embryo Viability of Group III Recipients as Determined by the Rosette Inhibition Test Post Embryo Transfer .......................... 96

V11l

LIST OF PLATES

Plate Page

1 Steps in the Embryo Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 28

2 Micrograph (x1 60) of E-rosettes Between Cattle Lymphocytes And Sheep Red Blood Cells . . . . . . . . . . . . . . 43

3 Viable Transferable Embryos Recovered Seven Days After Oestrus ( 400x) (A) Excellent Quality Blastocyst (B) Excellent Quality Compacted Morula (C) Good Quality Early Blastocyst (0) Fair Compacted Morula . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . 49

4 Non-transferable Immature And Degenerated Embryos Recovered Seven Days After Oestrus (400x) (A) Unfertilized Oocyte (B) 4-ceU Embryo (C) 8-cell Embryo And (0) Degenerated Compacted Morula . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . 50

IX

Abstract of thesis submitted to the Senate of University Putra Malaysia in fulfilment of the requirement of Master of Science.

EMBRYONIC DEATHS IN THE SAHIW AL FRIESIAN COWS IN AN INSTITUTIONAL FARM

IN MALAYSIA

by

ROSLAIN1 BT.HJ. RUSLI

APRIL 1998

Chairman: Dr. Abd. Wahid bin Haron

Faculty : Veterinary Medicine and Animal Science

Reproductive wastage is a major cause of production loss in dairy animals.

Fertilization failure and embryonic death are suggested to be the main causes of

reproductive loss. The dairy industry in Malaysia is hampered by poor reproductive

performance which is manifested by repeat breeding and lengthened calving interval.

Whether this is due to fertilization failure or embryonic death has never been

determined. This study is belief to be the first in the tropics in trying to quantify reasons

x

for reproductive inefficiency in crossbred cows in the tropical environment and

attempts to relates the influence of the hot ambient tropical temperature and humidity

to embryonic mortality.

In this study reproductive inefficiency is caused by fertilization failure (9%),

luteal insufficiency at insemination (1 0%), embryonic mortality (53%) and foetal

deaths (8%). Embryonic mortality is the major caused of reproductive inefficiency.

BED contributed to 73% of all embryonic mortalities with 62% of these taking place

from Day 8-21 of the gestation period. Fertilization rate of81% is achievable in the

tropics. Treatment with exogenous progesterone do not increased pregnancy rate

neither does keeping early pregnant animal under stallfeeding, but both factors had a

positive association in contributing to embryonic mortality_

Poor reproductive performance in this study in not due to fertilization failure

but due to embryonic mortality. This study has challenged the traditionally accepted

reason of poor heat detection being the main reason for poor reproductive performance

(due to fertilization failure) in the Sahiwal Friesian cows.

Xl

Abstrak tesis yang di kemukakan kepada Senat Universiti Putra Malaysia bagi memenuhi syarat-syarat untuk Ijazah Master Sains.

KEMATIAN EMBRIO DI DALAM LEMBU KACUKAN SAHIW AL FRIESIAN DI SEBUAH LADANG

DI MALAYSIA

oleh

ROSLAINI BT. ill. RUSLI

April 1998

Pengerusi : Dr. Abd. Wahid bin Haron.

Fakulti : Kedoktoran Veterinar dan Sains Peternakan

Kerugian di sebab kegagalan untuk melahirkan anak pada jangka masa yang

ditetapkan didalam penternakan lembu tenusu adalah tinggi. Antara sebab

kemungkinan bolih berlaku adalah kegagalan untuk persenyawaan ova dan kematian

embrio pada peringkat awal kebuntingan. Industri tenusu di Malaysia mengalami

masalah pembiakan lembu yang tidak ekonomik dimana jangka selang kelahiran yang

panjang dan lembu kerap mengulang untuk dibiakkan. Samada keadaan ini disebabkan

olih kegagalan untuk persenyawaan atau kematian embrio peringkat awal kebuntingan

tidak pernah diselidiki. Kajian ini adalah yang pertama di jalankan di tropik untuk

Xli

menentukan faktor faktor penyebab di samping mengaitkan kelembapan dan cuaca

iklim tropik.

Kajian ini mendapati kekurangan fungsi luteal selepas permanian beradas

(10010), kegagalan persenyawaan (9%), kematian embrio (53%) dan kematianjanin

(8%) adalah faktor penyebab kepada masaalah pembiakan lembu. Sebanyak 73% dari

kematian embrio berlaku pada peringkat awal kebuntingan dimana 62% darinya berlaku

antara hari ke-8 hingga hari 21 kebuntingan. Kadar persenyawan yang tinggi (81 %)

bolih dicapai di bawah iklim tropik. Memberi rawatan hormon progesterone dan

menyimpan ternakan di dalam kandang pada peringkat awal kebuntingan tidak

berkesan untuk meningkatkan kebuntingan, tetapi kedua-dua faktor mempunyai kaitan

yang tinggi dengan kematian embrio.

Masaalah pembiakan di dalam kajian ini hukan disebabkan olih kegagalan

persenyawaan ova tetapi kerana kematian embrio pada peringkat awal kebuntingan.

Keputusan dari kajian ini telah mencabar pendapat yang di terima umum bahawa

kegagalan mengesan berahi (menyebabkan kegagalan persenyawaan ova) adalah

penyebab utama kepada masaalah pembiakan di dalam lembu kacukan Sahiwal Friesian.

xiii

CHAPTER I

INTRODUCTION

About half of the world's cattle populations are located in the tropics.

However, they managed to only produced less than one third of the world's milk and

meat supply. Their productivity is limited by low reproductive rates, unfavourable

environmental conditions and less efficient management practices.

In 1974, the dairy development programme was launched by the Department

of Veterinary Services (DVS) based on the requirements of the New Economic Policy

(NEP), to supplement the income of farmers through dairying activities. To organise

and coordinate the dairy operation and all extension activities in dairy development

areas (DDA), the DVS has established 40 milk collecting centres (MCC) by 1992 with

a total of 7,500 farmers participating in the programme. Today [1994] 3000 farmers

were estimated to be still active in dairying. A total of20,000 Sahiwal Friesian heifers

have been imported between 1975 - 1991 for the dairy programme, out of which

14,708 dairy crossbred cows and heifers were distributed to farmers through the

MCC's at subsidised government rates (Mustaffa-Babjee, 1994).

All cooperative members are eligible to all services from marketing their milk

products, before and advanced dairy training at established government institution,

subsidise rate of dairy stocks for initial purchase and replacements, an extension

1

2

services which includes artificial insemination and disease control and lastly an

organised computation of animal's reproductive and production records at the MCC's.

It was hoped that an eventual outcome of this programme, is that the dairy industry in

Malaysia will be able to cater 20% of its local milk needs by the year 2000. However

the rate of self- sufficiency of milk was only 4.3% (Osman, 1993).

Sharif uddin et al. (1983) found that dairy crossbreds belonging to the

smallholder farmers experienced a period of post-partum anoestrus ranging from four

to ten months. The longer calving intervals experienced in the small-holder dairy herds

were due to inactive ovaries rather than failure to detect heat (Sharifuddin et aI.,

1985). This was significantly associated with the use of calves to stimulate milk-let­

down by the small-holder farmers (Sharifuddin et aI. , 1986). Iainudeen and Salim

(1994) concluded that the major fertility problems of village cattle in the tropics were

poor estrus detection, repeat breeding, and prolonged calving-to-conception interval.

Delayed puberty was also suspected to be contributing to the problems, as it shortens

the production lifetime and reduced the number of lactations and calves per cow .

Reproductive wastage is a major cause of production loss in both dairy and

beef cow herds. Fertilisation failure and early embryonic mortality are suggested to be

the main causes of this reproductive wastage, and in dairy herd performance it is

manifested by repeated breeding and long calving intervals. An analysis of the breeding

records maintained by a computer recording system (Dairy Champ, Univ. Of

Minnesota) it was found that the calving-to-conception interval of the Malaysian dairy

crossbred cattle in two institutionalised farms in Kluang were 131 ± 15 days and 134. 9

± 9 days and services per conception rate of3.3 6 ±0. 9 and 3.57± 0.5, respectively.

3

There is clear evidence of repeated services for a cow to conceive. Whether the reason

for poor reproductive performance is due to fertilisation failure or early embryonic

deaths, need to be established.

Dairy farming in Malaysia receives stiff competition from the plantation sector.

Major lands are allocated for rubber, oil-palm and industrial estates, and dairying now

occupies marginal lands not large enough for other uses. There is a need for a major

shift from extensive system to intensive system of farming. How the reproductive

performance of dairy cows will be affected under intensive tropical farming condition

is still unknown and need to be studied.

Three reproductive diagnostic tools, namely the embryo recovery technique to

determine the fertilization rate, the progesterone radioimmunoassay procedure for

assessing luteal function and the rosette inhibition test for detection of early pregnancy

factor (EPF) have been used in two experiments.

The objectives of the present studies were as follows:

In Experiment 1, the objectives were:

(a) to establish the fertilization rate of the Sahiwal-Friesian cows,

(b) to study the stage and patterns of embryonic deaths,

(c) to study the factors that contribute to reproductive inefficiency in this herd.

In Experiment 2, the objectives were:

(a) to study the effects of stall feeding and exogenous progesterone

supplementation on the conception rates of Sahiwal Friesian cows.

CHAPTERll

LITERA TURE REVIEW

The Reproductive Performance of Sahiwal-Friesian Cows in the Tropics

The dairy industry in Malaysia is mainly limited to small scale fanning. Dairying

as an enterprise and/or business was brought along by the migrants Indians from India

and has remain an activity identified with the Indian community. The dairy cattle

population in Malaysia originated from a mixture of Indian zebu breeds and has been

designated as the Local Indian Dairy (LID) cattle (Mustaffa-Babjee, 1994). S ince the

implementation of the dairy development programme, 20,000 heads of Sahiwal-

Friesian heifers were imported from Australia and New Zealand to form the base

stock. Gradual upgrading of the cattle through breeding, selection and progeny testing

is in progress towards producing a type of cattle totally adapted to the hot humid

conditions in Malaysia.

Conception Rate

Alexander et al. (1984) reported that conception rates in the Australian

Sahiwal-Friesian cows was 77% after two inseminations. Sixty nine percent of all

inseminations were performed at less than 86 days post calving with an average period

of 106 days for calving-to-conception. Records from two institutionalised farms in

4

5

Malaysia with similar crossbreds were 21.9 to 39.3% and 22.3 to 51.8% respectively

for the past 10 years.

Calving Interval

The calving intervals in Sahiwal-Friesian cows were from 425.5 ±129.5 days

in stallholders herd in Malacca (Abu Hassan and Nazri, 1993), 407 days (Eusof and

Ngah, 1982), 442 ±12 days (Normala, 1995) for smallholder herds in Banting and

407.0 ±12.7 in Keningau (Normah, 1988). Supriatna (1989) and Surachat (1989) both

reported a calving interval of 405±80 days and 452 to 486 days for small holders dairy

herds in West Java and North-east Thailand respectively.

On a larger scale of production, two institutionalised dairy farms in Kluang

Johore recorded an average of 411± 14.8 days and 414.9 ± 8.8 days respectively, from

1986-1995.

Reproductive Efficiency

Rao et al. (1981) reported their finding on crossbred cows that the frequency

of silent heat (39.3%) and percentage of ovulatory failure (41.0%) during the second

oestrous cycle after calving were still high, but in the third ovulation which occurred

about 20.3 ± 0.8 days after second ovulation the values decreased to about 25.9% and

14.8% respectively. Singh et al. (1981) found that factors affecting conception were

anestrus (11.5%) and repeat breeding (25.0%) in 148 halfbred Sahiwal-Friesian cows,

while those affected by parturition resulted from retention of placenta (8.1 %), abortion

(4.1%) and stillbirth (3.4%), making a total of about 15.6%. Normala (1995) reported

a mean pregnancy rate of 87.7% and an abortion and stillbirth rate of 1.9% and 2.9%

6

respectively from 31 smallholder herds around Banting. The report also cited that

dystocia, retained placenta and repeat breeding as the main reproductive problems

encountered.

Koh (19 75), attempted to quantify some of the reproductive parameters that

contribute to infertility in a herd from records maintained by the Institution's farm. He

found that the percentage of fertilisation failure was 30.9 %, and embryonic and early

fetal mortality was 30.7%. The abortion rate was 0.7% and a calving percentage of

26.3% in a temperate crossbred group. Jainudeen et aI. (1985) in a study involving 186

SahiwaI-Friesian and Friesian-LID cows observed a significant difference in the service

period among parity, body conformation and nutrition groups. In Thailand, during the

same period, repeat breeding in a similar crossbred was related to the management

system (Songsasen et aI. , 1986)

Factors Influencing Reproductive Performance

Reproductive performance of cattle is relatively low in many of the developing

countries and remains a major limitation to the achievement of optimum efficiency and

economic production. The reasons for this are multiple and interrelated but may be

listed as nutritional, environmental, disease and management factors (peacock, 19 71

and Peters, 199 6). Reproductive performance, as described by Coleman et aI. (1 985),

is a measure of the ability of a cow to become pregnant and produce viable offsprings.

Under most conditions the optimum calving interval is 365 days or thereabouts. Poor

fertility results in losses due to lower milk sales, fewer calves born and slower genetic

progress.

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The calving interval is the parameter mostly used to asses reproductive

efficiency and is composed of the calving to conception interval and the gestation

period. Of these the calving to conception interval is the critical variable and in tum

consists of:

1) the time to resumption of ovarian cycles (the acyclic period);

2) the occurrence and detection of oestrus;

3) the fertility at service.

Reproductive inefficiency is manifested clinically by anoestrus and repeat

breeding. The acyclic period or delayed onset to resumption of ovarian cycles after

calving is affected by certain diseases of the puerperium, nutrition and management.

Repeat breeding are caused by fertilisation failure or embryonic death.

Factors Affecting the Acyclic Period

Diseases of the Puerperium

Thompson et al. (1983) showed that cows with calving difficulty (dystocia) had

longer calving to first service and conception intervals. Similarly, Borsberry and

Dobson (1989) found that retain placenta (RPM) and endometritis extended calving

to conception intervals by 60 days. Uterine abnormalities including metritis have been

shown to be associated with high circulating PG concentration and that the first

ovulation post partum does not occur until PG levels have returned to baseline (Madej

et aI., 1984). Risco et al. (1994) reported that milk fever (hypocalcemia) resulted in

extended calving to conception intervals by delaying time of first ovulation post partum

and this is associated with delayed involution. Fatty liver disease affects reproductive

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performance by delaying ovarian cyclicity post partum and low conception rates

(Higgins and Anderson, 1983; Reid et al., 1 983).

Cystic ovarian disease also commonly occurs in dailY cows in early lactation

and is responsible for delays in rebreeding. Estimates of incidence of cystic ovaries in

zebu cattle range from 1 to 13% (Rao et al., 1965). There appears to be a genetic

predisposition to cystic ovaries. Animal of all ages are susceptible. Hemendez­

Ledezma et al. (1984) observed that the incidence of cystic ovaries increased from

8.4% in primiparous cows to 25.9% in cows in their fifth lactation. The incidence

overall was also higher in cows with metritis (14.6%) and in retained placenta (1 3.6%)

than in healthy cow.

Nutrition

Most of the research on nutrition and fertility has focus on the development of

feeding dietary regimes that will support milk production at an economic level and

maintain cow health and reproductive performance. The dairy cows in early lactation

has a higher energy requirement than can be supported by intake and is always in

negative energy balance (NEB). The level of NEB is correlated both with milk yield

and timing of the first ovulation post partum (Ducker et al., 1985; Butler and Smith,

1989). Canfield and Butler (1991) suggested that ovulation does not occur until the

energy balance begins to rise again. Extended period of anoestrus caused by under

nutrition was due to repeated development and atresia of dominant follicle. Stagg et

aI. (1995) found that mean interval from calving to first ovulation was 25 days longer

for those receiving 80 MJ as opposed to 120 MJ of metabolisable energy daily. The

body condition of cows at calving influences the interval of calving to first ovulation

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(Wright et aI., 1992). He demonstrated that thin cows on low (60 MJ ME daily) and

high (1 1 5 MJ ME daily) energy diets had longer calving to first post partum oestrus

as compared to fat cows given similar diet.

Low protein intakes can reduce the incidence of behavioural oestrus and

conception in beef cows (Robinson, 1996) due to stimulatory effects of digestible

undegradable protein (DUP) on milk production thus increasing the magnitude of the

deficit in energy balance. Suckler cows in poor body conditions fed with high DUP

diets at mating has longer calving to first oestrus interval (Sinclair et aI., 1 994).

Factors Contributing to Conception Failure

Fertilisation Failure

In cows with normal breeding histories fertilisation rate in excess of 80% are

generally achieved (Boyd et al., 1 969; Ayalon, 1979; O'Farrel et aI., 1 983 and Ahmad

et al., 1994). In repeat breeder cows fertilisation rate and embryo survival rate may be

as low as 56% and 23% ( Graden, 1968; Ayalon, 1 978 and O'Farrel et aI., 1983).

Failure to conceive is considered to be caused by fertilisation failure and early

embryonic mortality (Graden, 1968; Ayalon, 1978; O'Farrel et aI., 1 983 ; Maurier and

Chenault, 1983 and Gustafi'sson, 1985). Repeat breeding will eventually lengthens the

calving-to-conception intervals (Laming and Bullman, 1 976; Oltner and Edqvist, 1 98 1 ;

Haresign e t aI., 1983). Suboestrus and incorrect oestrus detection may result in

repeated irregular oestrus intervals. This can also be due to late embryonic or early

fetal deaths and other genital infections such as campylobacteriosis or infectious bovine

rhinotracheitis (IBR) infection (Noakes, 1988). The origin of non-infectious infertility

is often attributed to environmental influences and husbandry factors.

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Oestrus detection failure: Faulty oestrus detection is still a major factor

contributing to fertilization failure. In the tropics poor accuracy in oestrus detection

was due to the predominant zebu type of cattle do not display the overt signs of

oestrus (Galina et al., 1990). Oestrus expressions are influenced by group compositions

and group size, the hierachial status of the cows with the dominant cows less likely to

accept to be ridden (price, 1987). Galina et al. (1996) in reviewing the findings of other

researchers suggested that zebu type cows in oestrus have certain influence on their

herd mates. This was supported by observations of Gutierrez et al. (1993) and Larsen

and Kiracofe (1995) that non treated control cows are immitating behavioural signs of

oestrus of treated animals.

Environmental and Management Factors:

Rain, strong wind, herding or keeping animals accustomed to grazing under

corral conditions tends to suppress mounting or oestrus related activities (Vaca et aI.,

1988; Price, 1987). When temperature peak higher than 30°C mating behaviour was

less frequent (Gwazdauskas et aI., 1975) and oestrus cows tends to exhibit more

secondary signs in hot weather (pennington et aI., 1985) thus increasing oestrus

detection error rate. During heat stress period fertilisation failure was due to the effect

of heat stress on the oocyte during follicular development (Monty and Racowsky,

1987).

The incidence of cases of lameness in dairy cow herds caused reduced

reproductive efficiency. Lameness increases calving to first service and calving to

conception intervals ( Lucey et aI., 1986; Collick et aI., 1989) due to lame cows are

less inclined to exhibit oestrus due to pain. Britt et al. (1986) showed that cows housed

on concrete flooring showed less oestrus activities than those on straws.

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Timing of Insemination: Considerable technical skill is required for a

dairyman to detect oestrus. Some dairymen tend to detect oestrus based on secondary

overt signs like restlessness, bellowing, sniffing, swelling and reddening of the vulva

and mucous discharge. A cow standing to be mounted is the most definitive sign of

oestrus. Standing behaviour is critical because the onset of standing heat is closely

related to the time of ovulation (O'Connor and Senger, 1997). The highest conception

rates are obtained when cows are inseminated between the middle and end of the

period of oestrus (Roberts, 1971). Insemination carried out during the early part of

oestrus and after ovulation has occurred, resulted in lowered pregnancy (Boyd, 1970;

Deas, 1970).

Embryonic Mortality

Embryonic mortality is defined as deaths of the conceptus during the embryonic

period usually considered from conception to the completion of organogenesis which

is up to 45 days in cattle (Committee on Bovine Nomenclature, 1972). Abortion in

cattle is defined as the expulsion of living or dead foetus before 261days.

Reproductive wastage is a major inefficiency in all livestock production. The

occurrence and significance of embryonic mortality in farms animal has been

extensively reviewed by Ayalon (1978), Edey (1979) and Flint et al. (1982) in farm

species like cattle, sheep and pig respectively. A very large portion of the losses occurs

during the first 3 to 4 weeks and are designated as early embryonic mortalities. When

death occurs at this very early stage of pregnancy, the conceptus may be completely

resorbed by the uterus, or the vessicle may passed out through cervix and vagina and

usually escapes notice. Clinically the loss remains unrecognised as the loss occurs

before any fluctuation in oestrous cycle is obvious. Death of embryos before seven