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Genetic And Phenotypig Trends In Some Performance Traits Of Kajlli Sheep

By: Farman Ullah | Prof. Dr. Khalid Javed.
Contributor(s): Prof. Dr. Muhammad Abdullah.
Material type: materialTypeLabelBookPublisher: 2011Subject(s): Department of Livestock ProductionDDC classification: 1345,T Dissertation note: Kajli sheep is one of the native breeds and is found in the irrigated areas of central Punjab (Districts of Sargodha, Khushab, Gujrat, Mandi Baha-ud-Din, and Mianwali). Kajli sheep is mostly raised for mutton, wool and occasionally for milk production. Wide variation exists in various production and reproduction traits of Kajli sheep which indicates a great scope of improvement in these traits of economic importance. Any program of breed improvement is based on maximum exploitation of genetic variation. The potential of genetic improvement largely depends on genetic variation of the trait and its relationship with the other traits. Knowledge of heritability, repeatability and correlations among various traits is essential for formulating efficient breeding plan and selection strategies. Objective of this study is to evaluate the performance of a purebred flock of Kajli sheep maintained at Livestock Experimental Station Khushab and Livestock Experimental Station Khizrabad (Sargodha). Data on performance traits as Birth weight, Weaning weight, Yearling weight and Greasy fleece weight from 1994 to 2009 were collected, An effort was made to determine the effect of all environmental and non genetic factors on the performance of animals. For this purpose LSMLMW computer program was used. The genetic parameters i.e., heritability, and phenotypic and genetic correlations among various traits will be estimated. The breeding values for different traits were estimated for comparative ranking of animals. Phenotypic and genetic trend lines were drawn to assess the selection success in previous generations of Kajli sheep. These analyses were done using DFREML computer soft ware which is s pecially designed for the estimation of variance components. The information so generated will ultimately be helpful in developing future breeding plans for genetic improvement of Kajli sheep in Pakistan. The birth and weaning weight in this flock averaged 4.16±0.0Ikg and 18.70±0.08 kg whereas yearling weight was 37.52±0.06 kg. The pre weaning average daily gain was 142.34±0.83 gms. Birth weight varied significantly due to years, season, sex, type of birth and flock. Data showed non- significant interaction between sex and type of birth. Analysis of variance revealed significant effect of year of birth and season of birth on weaning weight. However, the difference due to sex is non-significant. Type of birth and age of the dam were significant. Effect of weaning age of the lambs on weaning weight was also significant, whereas, birth weight had a non significant effect (P<0.05) on weaning weight. The variation in body weight due to year, sex, and season of birth were significant (P<0.05).Whereas, effect of flock and type of birth were non- significant. Weaning age of the lambs and birth weight had a non significant (P<0.05) effect on yearling weight whereas weaning weights of the lambs had significant effects on the trait under consideration. The analysis of variance revealed that year and season of birth and birth type showed significant effect on pre weaning average daily gain while sex had non-significant effect on the trait. The regressions of weaning weight and birth weight on pre weaning average daily gain were significant (P<O.OI). The estimates of heritability for birth weight, weaning weight, yearling weight, pre-weaning average daily weight gain, and greasy fleece weight were 0.054±0.019, 0.069±0.016, 0.015±0.020, 0.056±0.016, and 0.170±0.060 respectively. The low heritability estimates indicated the presence of less additive genetic variance and large environmental variance. Hence, improvement in the traits through selection may be limited. The estimated breeding values for Khizerabad farm were, for birth weight from -0.205 to 0.164 kgs in males. The corresponding values were from -0.149 to 0.180 kgs in females. The estimated breeding value for weaning weight ranged from -1.029 to 1.822 kgs in males and corresponding values were from -1.205 to 1.555 kgs in females. The breeding value estimated for yearling weight was -0.152 to 0.285kg in males and -0.159 to 0.224kg in females. The estimated breeding value for pre weaning growth rate was -0.194 to 0.212 gms in males and -0.174 to 2.00 gms in females, and for greasy fleece weight it was -0.247 to 0.708 kgs and -0.429 to 0.575 kgs in males and females respectively. The estimated breeding values for Khushab farm were, for birth weight from -0.157 to 0.173 kgs in males. The corresponding values were from -0.148 to 0.145 kgs in females. The estimated breeding value for weaning weight ranged from -1.478 to 0.284 kgs in males and corresponding values were from -0.976 to 1.923 kgs in females. The breeding value estimated for yearling weight was -0.198 to 0.176 in males and -0.166 to 0.170 in females. The estimated breeding value for pre weaning growth rate was -0.281 to 0.195 gms in males and -0.205 to 0.148 gms in females, and for greasy fleece weight it was -0.380 to 0.706 kgs and -0.267 to 0.590 kgs in males and females respectively. The estimated breeding values for sire in Khizerabad farm were, for birth weight ranged from -0.169 to 0.164 kgs. The estimated breeding value for weaning weight ranged from -1.029 to 1.694 kgs. The breeding value estimated for yearling weight was -0.151 to 0.285 kgs. The estimated breeding value for pre weaning growth rate was -0.190 to 0.212 gms, and for greasy fleece weight it was -0.146 to 0.520 kgs. The estimated breeding values for sire in Khushab farm were, for birth weight ranged from -0.157 to 0.173 kgs. The estimated breeding value for weaning weight ranged from -1.478 to 2.846 kgs. The breeding value estimated for yearling weight was - 0.198 to 0.176 kgs. The estimated breeding value for pre weaning growth rate was -0.281 to 0.195 gms, and for greasy fleece weight it was -0.335 to 0.706 kgs. The genetic trends for birth weight in Kajli sheep showed decreasing trend and phenotypic trend was fluctuating, whereas, the genetic and phenotypic trend for weaning weight showed fluctuating trend. For yearling weight genetic and phenotypic trend was also observed which show fluctuation, pre weaning growth rate also not statistic. The phenotypic trend for greasy fleece yield showed little increasing trend.
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Item type Current location Collection Call number Status Date due Barcode Item holds
Thesis Thesis UVAS Library
Thesis Section
Veterinary Science 1345,T (Browse shelf) Available 1345,T
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Kajli sheep is one of the native breeds and is found in the irrigated areas of central Punjab
(Districts of Sargodha, Khushab, Gujrat, Mandi Baha-ud-Din, and Mianwali). Kajli sheep is
mostly raised for mutton, wool and occasionally for milk production. Wide variation exists in
various production and reproduction traits of Kajli sheep which indicates a great scope of
improvement in these traits of economic importance. Any program of breed improvement is
based on maximum exploitation of genetic variation. The potential of genetic improvement
largely depends on genetic variation of the trait and its relationship with the other traits.
Knowledge of heritability, repeatability and correlations among various traits is essential for
formulating efficient breeding plan and selection strategies. Objective of this study is to evaluate
the performance of a purebred flock of Kajli sheep maintained at Livestock Experimental Station
Khushab and Livestock Experimental Station Khizrabad (Sargodha). Data on performance traits
as Birth weight, Weaning weight, Yearling weight and Greasy fleece weight from 1994 to 2009
were collected, An effort was made to determine the effect of all environmental and non genetic
factors on the performance of animals. For this purpose LSMLMW computer program was used.
The genetic parameters i.e., heritability, and phenotypic and genetic correlations among various
traits will be estimated. The breeding values for different traits were estimated for comparative
ranking of animals. Phenotypic and genetic trend lines were drawn to assess the selection success
in previous generations of Kajli sheep. These analyses were done using DFREML computer soft

ware which is s pecially designed for the estimation of variance components. The information so
generated will ultimately be helpful in developing future breeding plans for genetic improvement
of Kajli sheep in Pakistan. The birth and weaning weight in this flock averaged 4.16±0.0Ikg and
18.70±0.08 kg whereas yearling weight was 37.52±0.06 kg. The pre weaning average daily gain
was 142.34±0.83 gms. Birth weight varied significantly due to years, season, sex, type of birth
and flock. Data showed non- significant interaction between sex and type of birth. Analysis of
variance revealed significant effect of year of birth and season of birth on weaning weight.
However, the difference due to sex is non-significant. Type of birth and age of the dam were
significant. Effect of weaning age of the lambs on weaning weight was also significant, whereas,
birth weight had a non significant effect (P<0.05) on weaning weight. The variation in body
weight due to year, sex, and season of birth were significant (P<0.05).Whereas, effect of flock
and type of birth were non- significant. Weaning age of the lambs and birth weight had a non
significant (P<0.05) effect on yearling weight whereas weaning weights of the lambs had
significant effects on the trait under consideration. The analysis of variance revealed that year
and season of birth and birth type showed significant effect on pre weaning average daily gain
while sex had non-significant effect on the trait. The regressions of weaning weight and birth
weight on pre weaning average daily gain were significant (P for birth weight, weaning weight, yearling weight, pre-weaning average daily weight gain, and
greasy fleece weight were 0.054±0.019, 0.069±0.016, 0.015±0.020, 0.056±0.016, and
0.170±0.060 respectively. The low heritability estimates indicated the presence of less additive
genetic variance and large environmental variance. Hence, improvement in the traits through
selection may be limited. The estimated breeding values for Khizerabad farm were, for birth
weight from -0.205 to 0.164 kgs in males. The corresponding values were from -0.149 to 0.180
kgs in females. The estimated breeding value for weaning weight ranged from -1.029 to 1.822
kgs in males and corresponding values were from -1.205 to 1.555 kgs in females. The breeding
value estimated for yearling weight was -0.152 to 0.285kg in males and -0.159 to 0.224kg in
females. The estimated breeding value for pre weaning growth rate was -0.194 to 0.212 gms in
males and -0.174 to 2.00 gms in females, and for greasy fleece weight it was -0.247 to 0.708 kgs
and -0.429 to 0.575 kgs in males and females respectively. The estimated breeding values for
Khushab farm were, for birth weight from -0.157 to 0.173 kgs in males. The corresponding
values were from -0.148 to 0.145 kgs in females. The estimated breeding value for weaning
weight ranged from -1.478 to 0.284 kgs in males and corresponding values were from -0.976 to
1.923 kgs in females. The breeding value estimated for yearling weight was -0.198 to 0.176 in
males and -0.166 to 0.170 in females. The estimated breeding value for pre weaning growth rate
was -0.281 to 0.195 gms in males and -0.205 to 0.148 gms in females, and for greasy fleece
weight it was -0.380 to 0.706 kgs and -0.267 to 0.590 kgs in males and females respectively. The
estimated breeding values for sire in Khizerabad farm were, for birth weight ranged from -0.169
to 0.164 kgs. The estimated breeding value for weaning weight ranged from -1.029 to 1.694 kgs.
The breeding value estimated for yearling weight was -0.151 to 0.285 kgs. The estimated
breeding value for pre weaning growth rate was -0.190 to 0.212 gms, and for greasy fleece
weight it was -0.146 to 0.520 kgs. The estimated breeding values for sire in Khushab farm were,
for birth weight ranged from -0.157 to 0.173 kgs. The estimated breeding value for weaning
weight ranged from -1.478 to 2.846 kgs. The breeding value estimated for yearling weight was -
0.198 to 0.176 kgs. The estimated breeding value for pre weaning growth rate was -0.281 to
0.195 gms, and for greasy fleece weight it was -0.335 to 0.706 kgs. The genetic trends for birth
weight in Kajli sheep showed decreasing trend and phenotypic trend was fluctuating, whereas, the genetic
and phenotypic trend for weaning weight showed fluctuating trend. For yearling weight genetic and
phenotypic trend was also observed which show fluctuation, pre weaning growth rate also not statistic.
The phenotypic trend for greasy fleece yield showed little increasing trend.

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