universiti putra malaysia performance of gaur x cattle hybrids nor
TRANSCRIPT
UNIVERSITI PUTRA MALAYSIA
PERFORMANCE OF GAUR X CATTLE HYBRIDS
NOR AZMAN HAJI NGAH
FPV 1989 3
PERFORMANCE OF GAUR X CATTLE HYBRIDS
By
NOR AlMAN RAJ 1 NGAH
A Thesis Subaitted in Fulfil.ent of the Requireaents for the Degree of Master of Science in
the Faculty of Veterinary Medicine and Ani.al Science
Universiti Pertanian Malaysia
October 1989
This thesis is dedicated to
.Y wife. Zuriyani binti Yusof
.y two sona, Nor Azrin and Nor Azrai
and .y late daughter, Allahyarha.ah Azyan Hafra
for their patience. understanding and acral support.
ii
ACKNOWLEDGEMENTS
I �ould like to express my gratitude to my supervisor,
Associate Professor Dr . Haji Mohd Hilmi bin Haji Abdullah of
the Department of Animal Science, Faculty of Veterinary
Medicine and Animal Science, Universiti Pertanian Malaysia for
his keen interest, continous guidance, support and
encouragement rendered throughout the duration of this study.
I am grateful to Yang Berbahagia Datuk Dr. Ahmad Mus t a f f a
bin Haji Babjee, Director General of Veterinary Services for
granting the permission to use the facilities available at
Rancangan Daging Penusu Padang Hijau, Kluang , the trust and
encouragement given in conducting the breeding of the gaur x
cattle hybrids (Selembu) at the farm.
Special thanks are extended to Associate Professor Dr. Ali
bin Rajion, Professor M . R . Jainudeen, Professor P . K . Baseut and
staff at the Department 01 Animal SCience, universiti
Pertanian Malaysia for their valuable suggestions and
constructive criticism during the final preparation of this
iii
manuscript. Special thanks are also extended to Dr. Nazri bin
Salim for his guidance on the statistical analaysis and to Dr .
Mohd Zamri bin Saad for his precious time in the final editing
of this manuscript .
Sincere appreciation is given to En. Amat bin Aswadi of
the National Artificial Insemination Center , Kluang for his
assistance in the semen collection and evaluation. Further
acknowledgements are also due to En. Ahmad bin Mahamood, Dr.
Rosli bin Awaluddin, Dr. Abdul Latif bin Borhan and all the
staff of Rancangan Daging Penusu Padang Hijau for their help
and involvement directly or indirectly in conducting the
research and collection of data in the Seleqbu breeding
programme at the Padang Hijau Farm, Kluang. Further
acknowledgements are also due for the Zoo Negara, Kelang and
the Department of Wildlife and National Parks for their
assistance in the study involving the gaur.
The stenographic service of Puan Sohaila binti Abdul Karim
in the preparation 01 this thesis is greatly appreciated .
This manuscript and the work it represents could not have
been achieved without the patience, undestanding and moral
support of my wife, Zuriyani and .y two wonderful sons, Nor
Azrin and Nor Azrai.
iv
TABLE OF CONTENTS
PAGE
ACKNOWLEDGElIENTS i i i
LIST OF TABLES ix
LIST OF FIGURES xi
LIST OF PLATES xii
LIST o r ABBREVIATIONS xiv
ABSTRACT xv
ABSTRAK xvii
CHAPTER
1
2
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
LITERATURE REVIEW 7
Zoological Position of the Gaur and Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • . 1
Breeds and Types of Gaur and Cattle .... ... 10
Phenotypic Features of Gaur and Cattle . . . . 1 2
World Distribution o f Gaur . . . . . . .... ...... 14
Numerical Distribution of Gaur in Malaysia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • . . . 15
Chromosome Complement of Gaur. Caltle and Their Hybrids . . . . . . . . . • • • • • . . . . 16
Interspecific Hybridization . . . . . . . • • • • . . . . 1 9
"ale Reproductive Status . . . . . . . . . • • . . . . . . . 22
Breeding Soundness Evaluation . . . . • • . . . . . . . 23
v
Libido . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Jlating Behaviour . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Scrotal Circuaference . . . . . . . . . . . . . . . . . . . . . 27
Se.en Evaluation . . . . . . . . . . . . . . . . . • . . . . . . . . 28
Interpretation of Breeding Soundness Evaluation ...................... .'. . .. . . . . 33
Testicular Histology ... . . . . .. . . . . . . . . . . . . . 33
Performance under Natural Mating . . . . .. . . . . 34
Growth Performance . . . . . . . . . . . . . . . . . . . . . . . . 35
Liveveight at Different Ages .... . . . . . ..... 35 Birth Weight . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Weaning Weights . . . . . . . . . . . . . . . . . . . . . . . 37 Yearling Weight . . . . . . . . . . . . . . . . . . . . . . . 38
Average Daily Gain . . . . . . . . . . • • . . . . . . . . . . . . 39
Experimental Procedure . . . . . . . . . . . . . . . . . . . . 41
3 EXPERIMENT 1 COMPARISOM OM THE PHEMOTYPIC FEATURES OF THE GAUR, X CATrLE mRIDS AlfD THE SABIVAL-FRIESIAlf CROSSBRED CATrLE
Introduction 42
Naterial and Methods . . . . . . . . . . . . . . . . . . . . . 43
Results Phenotype of the Gaur .. . . . . . . . . . . . . . . 44 Phenotype of Sahival-Friesian Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . 48 Phenotype of Gaur x Cattle Hybrids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
vi
4 EXPERIMENT 2: EVALUATION AND COMPARISON OF THE
GRONTH PERFORMANCE BETNEEN GAUR X CATTLE HYBRIDS AND SANIWAL-FRIESIAN CROSSBRED CATTLE
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • S9
Material and Methods . . . . . . . . . . . . . . . . . . . . • . S9 Ani_als . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Manage.ent of Animals . . . . . . . . . . . . . . • . 60
Results
Mean Liveweights at Different Ages • . • • • . • • . . • • . . • • . • • • . . • • . . • • . • • 6S Average Daily Gain . . . . . . . . . . . . . . . . . . 67 Percentage Advantage in Li veweight . . . . . . . . . . . . . . . . . . . . . . . . • . 69 Growth Pattern . . . . . . . . . . . . . . . . . . . . . . 11
Discussion
Potential of Gaur x Cattle Hybrids as Meat Producers . . . . • • • • • • • 73 Growth Pattern . . . . . . . . . . . . . . . . . • • • • . 77
Su .. ary and Conclusion . . . . . . .... .... ...... 19
5 EXPERIMENT l: EVALUATION AND COMPARISON OF THE MALE REPRODUCTIVE STATUS OF GAUR X CATTLE HYBRID AND SlBlfAL-FRIESIAH CROSSBRED CATTLE
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . 80
Materials and aethods . . . . . . . . . . . . . . . . . . . • . 81 Libido and Mating Abil i ty . . . . . . . . . . . . . 81 Libido Scoring System . . . . . . . . . . . . . . • • . 82 Mating Ability Scoring System . . . . . . • • . 83 Testicular growth . . . . . . . . ............. 84 SeMen Evaluation and Collection . . . . . • . 84 Seaen Evaluation . . . . . . . . . . . . . . . . . . . • • . 81 Breeding Soundness Evaluation . . . . . . . . . 92
Results
Libido and Mating Behaviour 92
vii
Testicular Capacity (scrotal circullterence) ... . ......... . ... . .... . .. 95 Se.en Evaluation . . . . . . . . . . . . . . . . . • . . . . . 95 Breeding Soundness Evaluation ......... � 102
Discussion
Libido and Mating Behaviour .. . . . .. . . .. . 102 Scrotal Circu.ference . . . . . . . . . . . . • . . . . . 104 Se�n Evaluation . . . . . . . . . .. . . .... . .. . . . 105 Breeding Soundness Evaluation . . . . • . . . . . 108
Conclusion . . . . . . . . . .. . . ...... . . . . . . . . .. . .. 108
6 EXPSIIIIIIIT 4 :m PUrolllAllCE OF 1lAL!: AIID FOOL!:
1
GAUR 1 CATTL!: HYBRIDS OIIDEI NATURAL IlATING AIID CONPAIED TO SAlIIAL - FRIKSIAII CIOSSBRED CATTL!:
Introduction . . . . . . . . . . . . . . . . . . . . • . • . • . . . . . 110
Material and Methods 110
Results ................................... 112
Discussion . . . . . .. . . . . . . .. . .. . . . . ... . . . ... 115
Conclusion and RecOMaendation .... . . ....... 117
GEIIIlRAL cotICLUSlOli AIID RECOIIIIEIIDATIOliS 118
REFERENCES . . . . . . . . • • . . . . . . . . . . • • • • . . . . . . . . . . • . . . 121
APPENDICKS • • • • • • • • • . • . • • . . . . . . • . • • • • . . • • . . • • • . • . 149
BIBLIOGRAPHICAL SmrCB • • • • • • . . . . • • • • . • • • • • • • • . . . 151
viii
TABLE
I
II
III
IV
V
VI
VII
LIST OF TABLES
DISTRIBUTION OF THE MALAYAN GAUR IN THE STATES OF MALAYSIA
THE NUMBER OF GAUR X CATTLE HYBRIDS AND SAHIWAL-FRIESIAN CROSSBRED CATTLE UTILISED IN THE EVALUATION OF GROWTH PERFORMANCE STUDY
LIVEWEIGHTS OF GAUR X CATTLE HYBRIDS AND SAHIWAL-FRIESIAN CROSSBRED CATTLE (Mean •
Standard Deviation) kg/day
AVERAGE DAILY GAIN OF GAUR- X CATTLE HYBRIDS AND SAHIWALFRIESIAN CROSSBRED CATTLE (Mean ± Standard Deviation) kg/day
PERCENTAGE ADVANTAGE IN LIVEWEIGHTS OF THE MALE AND FEMALE GAUR X CATTLE HYBRIDS OVER THE MALE AND FEMALE SAHIWAL-FRIESIAN CATTLE
GRADING OF SPERMATOZOA MOTILITY
SOCI�Y SCORING SOUNDNESS
OF THERIOGENOLOGY SYSTEM FOR BREEDING EVALUATION
ix
�PAGE
17
62
66
68
70
89
93
VIII MATING BEHAVIOUR SCORE OF GAUR X 94 CATTLE HYBRIDS AND SAHIWAL
FRIESIAN CROSSBRED CATTLE
IX SCROTAL CIRCUMFERENCE (em) or 96 GAUR X CATTLE HYBRIDS AND
SAHIWAL-FRIESIAN BULLS
X SEMEN CHARACTERISTICS OF GAUR X 97 CATTLE HYBRIDS AND SAHIWAL
FRIESIAN BULLS
XI INCIDENCE OF SPERM ABNORMALITIES 99 IN THE GAUR X CATTLE HYBRIDS AND
SAHIWAL-FRIESIAN BULLS
XII COMPARISON OF SPERM MORPHOLOGY 101 OF GAUR. GAUR X CATTLE HYBRIDS
AND SAHIWAL-FRIESIAN CROSSBRED
CATTLE (MICRON)
XIII BREEDING SOUNDNESS EVALUATION 103 SCORE FOR GAUR X CATTLE HYBRIDS
AND SAHTWAL-FRIESIAN DULLS
XIV THE NUMBER OF DIFFERENT METHODS 111 or CROSSING GAUR X CATTLE
HYBRIDS AND SARIVAL-FRIESIAN
BULLS
XV PREGNANCY WASTAGE IN THE GAUR X 113 CATTLE HYBRIDS.
x
FIGURE
I
2
LIST or FIGURES
ZOOLOGICAL POSITION OF THE GAUR
AND CATTLE
GROWTH PATTERN OF THE GAUR X
CATTLE HYBRID AND SAHIWAL-FRIESIAN
PAGE
8
72
PLATE
1
2
l
4
5
6
7
8
9
10
1 1
LIST or PLATES
LATERAL rACIAL REGION or GAUR
LATERAL FACIAL REGION OF SAHIWAL-FRIESIAN CATTLE
LATERAL rACIAL REGION OF GAUR X CATTLE HYBRIDS
FOREHEAD AND HORNS OF GAUR
FOREHEAD AND HORNS SAHIWAL-FRIESIAN CATTLE
OF
FOREHEAD AND HORNS OF GAUR X
CATTLE HYBRIDS
PHENOTYPE OF ADULT MALE GAUR
PHENOTYPE OF ADULT "ALE SAHIWAL-FRIESIAN CATTLE
PHENOTYPE OF ADULT MALE GAUR X CATTLE HYBRIDS
PHENOTYPE OF ADULT FEMALE GAUR
PHENOTYPE OF ADULT FEMALE SAHIWAL-FRIESIAN CATTLE
xii
PAGE
46
46
46
47
47
47
49
49
49
50
50
12
]J
14
15
16
11
18
19
PHENOTYPE OF ADULT FEMALE
GAUR X CATTLE HYBRIDS
PHENOTYPE OF NEW BORN GAUR X CATTLE HYBRIDS
PHENOTYPE OF NEW BORN SAHIWAL-FRIESIAN CATTLE
PHENOTYPE OF GAUR WEANER
PHENOTYPE OF SAHIVAL-FRIESIAN WEANER
PHENOTYPE OF GAUR X CATTLE HYBRID WEANER
MORPHOLOGY OF SPERMATOZOA A. GAUR B. SARIWAL-FRIESIAN CATTLE C. GAUR X CATTLE HYBRIDS
PHENOTYPE OF F2 GAUR X CATTLE HYBRIDS
xiii
50
51
51
53
53
53
100
114
SF
Fl HYBRIDS -
PKC
CMR
BSE
ICUN
LIST OF ABBREVIATIONS
SAHIVAL FRIESIAN
GAUR X CATTLE HYBRIDS
PALM KERNEL CAKE
CALF MILK REPLACER
BREEDING SOUNDNESS EVALUATION
INTERNATIONAL UNION FOR CONSERVATION or NATURE AND NATURAL RESOURCES
xiv
Abstract of the thesis presented to the Sen�le of Universiti Pertanian Malaysia in ful f i lment �t the
require.ent for the Degree ot Master ot Science
PERFOIXAJCE OF GAUR X CATTLE HYBRIDS
by
Nor Azaan bin 8aj1 Ngab
October 1989
Supervisor Assoc . Prof . Dr Haji Mohd Hilmi Abdullah, Ph . D .
Faculty Veterinary Medicine and Animal Science
The phenotype, growth perfor.anee and the reproduc tive
status of 60 heads of �ale and fe.ale gaur x cattle hybrids
were recorded and coapared with Sahiwal-Friesian c rossbred
cattle.
The .ain objectives of this experi.ent were to evaluate
the phenotype of the hybrids, the growth potential for beef
produc tion and to assess the reproduc tive capabilities of these
hybrids for future propagation.
xv
The present result shoved that the phenotypic features
could be utilised to identify this gaur x catlle hybr.�s . They
showed similar growth pattern as the Sahiwal-friesian crossbred
cattle indicating a faster growth rate at any phases of the
growth curve. The fast growth rate and high carcass value of
the gaur x cattle hybrids indicate that these animals have the
potential for beef production.
The gaur x cattle hybrids were not sterile as speculated.
The aale hybrids showed normal libido and .ating behaviour
but rated as questionable potential breeders due to the saall
scrotal circuaference, high incidence of spera abnoraalities
and poor spera quality. Natural aating
hybrids were related to low pregnancy
involving the aale
rate with a high
incidence of pregnancy wastage, therefore not suitable for use
as breeding bulls. However the fe.ale hybrids can aaintain
nor�al pregnancy, produce high calf crop and normal calf which
indicate that they were not affected by the interspecific
hybridization and aay be used for the propagation of these
ani.als.
xvi
Abstrak tesis yang dikemukakan kepada Senat Senat Universiti Pertanian Malaysia sebagai
.emenuhi keperluan Ijazah Haster Sa ins
IEUPAYAAN lACUIAN SELADANG X LEMBU ( SELENBU )
oleb
Mor Azaan biD Raj1 Igab
Oktober 1989
Penyelia Prof . Hadya Dr. Haji Hohd Hilmi Abdullah, Ph . D .
Fakulti Kedoktotan Veterinar dan Sains Peternakan
Ciri-ciri pegenalan fizikal (fenotaip) , kadar tumbesar dan
status peabiakan untuk 60 ekor (jantan dan betina) kacukan
seladang x le.bu (Sele.bu) telah dianalisa dan dibandingkan
dengan le.bu-Ie.bu kacukan Sahival-Friesian (SF) .
Objektif-objektif uta.a kajian ini adalah untuk menilaikan
fenotaip kacukan tersebut , potens} pertuabuhan untuk
pengeluaran daging dan .enentukan keupayaan pe.biakan Sele.bu
untuk .ena.bahkan bilangan pada masa akan datang.
xvii
Keputusan aval menunjukkan ciri-ciri fenotaip boleh
digunakan untuk mengenalpasti kacukan Seladang x Ie.bu . Mereka
mempunyai corak tumbesaran yang serupa dengan le�t.: kacukan
Sahival-Friesian tetapi telah menunjukkan Kadar tumbesaran yang
lebih cepat dan nilaian karkas yang tinggi bagi Selembu
aenunjukkan bahawa ternakan ini mempunyai potensi
pengeluaran daging.
adalah didapati tidak mandul saperti
untuk
yang
diagakkan. Selembu jantan .enunjukkan libido dan ciri-eiri
_engavan yang normal tetapi diletakkan dibavah keupayaan
potensi pembiakan yang dipersoalkan kerana mempunyai lilitan
scrotal yang keeil , terdapat banyak sperMa yang tidak normal
dan kualiti sperma yang kurang baik.
melibatkan Sele_bu jantan .enunjukkan
Kacukan tabii yang
kaitan dengan Kadar
kebuntingan yan� rendah dan pembaziran kebuntingan dan tidak
sesuai digunakan sebagai jantan pembiak. Tetapi Selembu bet ina
boleh mengandung. menghasilkan anak yang normal dan ini
.enunjukkan yang mereka tidak terlibat dalam masaaalah kacukan
di antara spesis (interspesifik) dan boleh digunakan untuk
.ena_bahkan bilangan ternakan ini .
xviii
CHAPTER 1
INTRODUCTION
In 1974, the Malaysian Govern.ent through the DeDartqent
of Veterinary services (DVS) had decided a target of 80\ self
sufficiency tor beet by 1990. Since then the DVS had embarked
on various programmes in trying to increase and improve meat
production towards achieving this goal.
that had been i.pleaenled were:
Among the progranmes
a) up grading the s.all local indigenous Kedah-Kelantan
(KK) cattle by crossing thea with the larger exotic or
improved breed of cattle through natural aating and
artificial inseminations with the hope of establishing
new breeds of beef cattle,
h) importation of feeder calves for feedlot schemes. both
in the government farms and smallholder schemes,
c) importation ot frozen meat to satisfy the country's
de.and for animal protein and
d) utilization of dairy calves for slaughter.
When an interesting incident took place in one of the DVS
farms. the DVS has decided to add that as a special prograa.e
to the existing progra .. e s . This incident occured in early
1
2
April, 1983 at Padang Hijau Farm. Kluanq where a lone gaur (Bos
qaurus hubbacki) or locally known as the Seladang, �et and
aated a "group of crossbred dairy heifers (Bas indicus x Bos
taurus) . As a result of this chance mating, 12 calves were
born on the fara. which calves look phenotypically dif ferent
from normal calves (Ah�ad Mabamood, 1984) . Thus, blood samples
were sent to the Cytogenetic Laboratory. Faculty of Veterinary
Medicine and Ani.al Science. Universiti Pertanian Malaysia tor
chro.osome analysis.
The karyotype of these calves were analysed and found to
possess chromosoae complement 2n=58 , a complement different to
that of their parents; the chroaosoee complements [or the
crossbred heifers were 20=60 wbile tbe gaur were 2n=56 (80ngso
and Hilmi, 1989) . Since the cbro�osome comple.ents of tbese
calves were intermediate to that of the dam (Sahiwal-Friesian)
and the sire (Gaur) , these new born calves were confirmed to be
hybrids of interspecific hybridization between gaur and cattle.
The resulting gaur x cattle hybrids were shown, on preliminary
observation, to exhibit better productivity than crossbred
cattle by showing better growth rate and bigger body size.
They also showed no difficulties in the local envieo.ent . with
this characteristics, the Fl hybrids were thought to have
potential for increasing beef production in Malaysia. A special
progra .. e involving the interspecific hybridization between
J
Sahiwal-Friesian crossbred cows to the gaur sire was created by
the DVS at the Padang Hijau Farm. The main objectives laid
dovn for this programme were :
a) to increase the number of gaur x cattle hybrids by
allowing the crossbred cattle to mate with the lone
gaur on the far. as wel1 as using other sources of
gaur in the country through natural mating or
artificial iose.ination,
b) to deter.ioe the growth performance of gaur x cattle
hybrids at different phases of growth under dif ferent
planes of nutrition and ca.pare these values with
those of cattle.
c) to deter.ioe and co.pare carcass characteristics and
dressing percentage between the gaue x cattle hybrids
and cattle.
d) to assess the reproductive status and breeding
potential of the hybrids for continous propagations
of gaur x cattle crossbreds,
e) to investigate the possible barriers o( hybridization
through chro.osa.al studies and
f ) t o e.bark on the conservation of a gene pool of gaur
x cattle hybrids by backcrossing and upgrading.
4
Hybridization between two different species (interspecific
hybridization) often takes place at experimental stations or by
chance matinq under natural condition. The resulted male or
female hybrids are often associated with problems related to
reproductive capabal ities although occassionally their
fertility may not be affected (Gray, 1957) . Host hybrid
. animals. particularly those with different chromosome
co.plement between two species are typically sterile
(B,enirschke. 1967) , as observed in the case of crosses between
the horse and donkey (Me Govern, 1976) . Even when the
chromosomes 01 the hybrids are apparently identical, fertility
.ay be effected (Basrur and Hoon, 1961) . Haldane (l922)
predicated that if such fertility problems were to occur, the
heterogametic rather than the homogametic sex should be
adversely affected. The prediction has been borne out in the
males of bison (Bos bison) x domestic cow (Bas taurus) hybrids
(Basrur and Moon, 1961) , yak (Boa qrunniens) x domestic cow
hybrids (Popescu, 1969) ,
1961) zebra cross horse
mule x hinny hybrids {Benirschke,
hybrids (King. 1967) and female
peregrine talcon x pairie falcon hybrids (Schmutz and Oliphant,
1981). However, report by Frechkops (1964) on equine hybrids
buffaloes vith different chromosome co.plements. The gaur (80S
qaurus) x crossbred cattle (80S taurus/80S indicus) ',Iybrids
with 2 pairs of unidentical chromosoaes may have impaired
fertility as reported in other species.
Before embarking on extensive breeding programme, a proper
and concise study should be done to assess its potential and
·viability. So far, other than scattered preliminary
observations on the gaur x cattle hybrids and other hybrids,
little study has been done in Malaysia or elsewhere to (urther
justify the hybrids propagation programme.
The present �tudy ��s divided into 4 experiments with a
specific objective for each experiment:
a) Experiment 1 roaparison of the phenotypic features
of the gaur, the Sahhal-Friesian cattle and the gaur
x cattle hybrid.
Objective To establish identHication
characteristics of the gaur x cattle hybrids.
b) Experillent 2 : The evaluation and comparison on the
growth performances between the Sahiwal-Friesian
crossbred cattle and the gaur x cattle hybrids.
Objective : To evaluate the beel potential of the gaur
x cattle hybrids.
6
c) Experiment) Evaluation and comparison on the lRale
reproductive status of the gaur x cattl.� hybrids
and Sahi�al-rriesian crossbred cattle using the
breeding soundness eValuation technique (8SE).
Objective To deter�ine the reproductive
capabilities of the male gaur x cattle hybrids.
d) Experiment 4 Comparison between the reproductive
perforMances of male and fe.ale gaur x cattle hybrids
under natural Mating condition and the perforMance of
Sahiwal-Friesian cattle.
Objective : To determine the reproductive perfor.ance
ot .ale and female gaur x catlle hybrids.
The results obtained frOB this study should provide
sufficient basic information Lo help forMulate an appropriate
breeding policy through hybridization ai�ed at increasing the
productivity of beef and conservation of the gaur which is now
considered an endangered species.