Genetic factors influencing feed efficiency in pure and crossbred broiler rabbits
By: Kasiviswanathan D.
Contributor(s): Raghavan K C (Guide).
Material type:
BookPublisher: Mannuthy Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences 2000DDC classification: 636.082 Online resources: Click here to access online Dissertation note: MVSc Abstract: An experiment was carried out to study the genetic and non-
genetic factors influencing feed efficiency (feed g/gain g) in broiler rabbits
viz. New Zealand White (NZW), Soviet Chinchilla (SC) and SC x NZW
crossbreds (CB). The non-genetic factors induded were sex, litter size at
birth, season and year of birth. The data pertaining to fortnightly body
weight from four to 12 weeks of age, feed efficiency (FE) and daily gain
(OG) were subjected to least squares analysis.
Breed had significant effect on body weights at all ages. NZW
had the least body weights through out the experiment and SC and CB did
not differ significantly at market age of 12 weeks. Overall daily gain was
not affected by breed while FE was significantly (P.:: 0.01) influenced by
breed. CB had the highest FE followed by SC and NZW rabbits. Dressing
percentage was highest (48.91) for CB compared to NZW and SC.
Crossbred rabbits exhibited a heterosis of 1.6 and 9.3 per cent for iz"
week body weight and FE respectively over the pure bred parents.
Sex was not a source of variation for any trait except for body
weight at weaning (four weeks). Litter size at birth had significant effect on
body weights at all ages but had no effect on overall OG and FE. Season
and year of birth influenced body weights at early ages only and had no
effect on overall OG and FE.
Estimates of heritability by sire + dam component of variance were
moderate to high for body weights at different ages, high for DG and not
different from zero for FE. Phenotypic correlations among body weights at
different ages were high and significant and genetic correlation estimates
were higher in magnitude for later ages. Phenotypic and genetic correlation
of FE with twelfth week body weight and DG were near to zero.
The present study indicated that breed is a significant source of
variation affecting body weight from four to 12 weeks of age and FE in
during period. CB rabbits though did not differ from SC for 1 z" week body
weight excelled the pure breeds when FE and dressing percentage are
considered. In monetary terms CB rabbits are found to be superior by 1.6
and 1.43 times over NZW and SC rabbits. So, crossbreeding of SC and
NZW rabbits is advocated for profitable commercial broiler rabbit production.
| Item type | Current location | Call number | Status | Date due | Barcode |
|---|---|---|---|---|---|
Theses
|
KAU Central Library, Thrissur Theses | 636.082 KAS/GE (Browse shelf) | Available | 171683 |
MVSc
An experiment was carried out to study the genetic and non-
genetic factors influencing feed efficiency (feed g/gain g) in broiler rabbits
viz. New Zealand White (NZW), Soviet Chinchilla (SC) and SC x NZW
crossbreds (CB). The non-genetic factors induded were sex, litter size at
birth, season and year of birth. The data pertaining to fortnightly body
weight from four to 12 weeks of age, feed efficiency (FE) and daily gain
(OG) were subjected to least squares analysis.
Breed had significant effect on body weights at all ages. NZW
had the least body weights through out the experiment and SC and CB did
not differ significantly at market age of 12 weeks. Overall daily gain was
not affected by breed while FE was significantly (P.:: 0.01) influenced by
breed. CB had the highest FE followed by SC and NZW rabbits. Dressing
percentage was highest (48.91) for CB compared to NZW and SC.
Crossbred rabbits exhibited a heterosis of 1.6 and 9.3 per cent for iz"
week body weight and FE respectively over the pure bred parents.
Sex was not a source of variation for any trait except for body
weight at weaning (four weeks). Litter size at birth had significant effect on
body weights at all ages but had no effect on overall OG and FE. Season
and year of birth influenced body weights at early ages only and had no
effect on overall OG and FE.
Estimates of heritability by sire + dam component of variance were
moderate to high for body weights at different ages, high for DG and not
different from zero for FE. Phenotypic correlations among body weights at
different ages were high and significant and genetic correlation estimates
were higher in magnitude for later ages. Phenotypic and genetic correlation
of FE with twelfth week body weight and DG were near to zero.
The present study indicated that breed is a significant source of
variation affecting body weight from four to 12 weeks of age and FE in
during period. CB rabbits though did not differ from SC for 1 z" week body
weight excelled the pure breeds when FE and dressing percentage are
considered. In monetary terms CB rabbits are found to be superior by 1.6
and 1.43 times over NZW and SC rabbits. So, crossbreeding of SC and
NZW rabbits is advocated for profitable commercial broiler rabbit production.
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