| Titles |
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English :
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Selection indexes for genetic improvement of body weight at 12 month of age in Egyptian buffaloes
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Arabic :
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ادلة انتخاب للتحسين الوراثى لوزن الجسم عند عمر 12 شهر في الجاموس المصرى
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| Abstract |
Data on birth weight, body weights at 3, 6, 9 and 12 months of age and daily gains from birth to weaning and from weaning to 12 months for 96 male and 148 female buffalo calves progeny of 27 sires and 192 dams were used to construct selection indexes to
improve body weight at 12 months of age .
Estimates of genetic and phenotypic parameters for the se data were calculated from paternal half-sib components of variance and covariance .The heritability estimates were 0.49, 0.10, 0.44, 0.69, 0.95, 0.02 and 0.89 for body weight at birth,3, 6, 9, 12, pre-and post-weaning average daily gain, respectively.
Genetic correlations of weaning weight with subsequent weights at 6,9 and 12 months were 0.98, 0.89 and 0.96, respectively; those of yearling weight with weights at 3, 6 and 9 months were 0.96, 0.97 and 0.91 respectively. The correlation of yearling weight with post -weaning average daily gain was close to one.
Fourteen selection indexes were constructed using different combinations of growth-related traits to improve the 12-month body weight. The maximum accuracy of selection (r TI =0.63)was obtained using the index (I 1 )incorporating body weight at birth,3,6,9 and 12 month of age .Selection for W12 (I 6 )alone would be more efficient (r TI =0.48)than selection for W9 (I 5 )
(r TI =0.40)alone or W6 (I 4 ) (r TI =0.35)alone.
The maximum expected genetic gain in 12-month body weight was 8.85 kg/generation when all five body weights were included in the index; this decreased to 8.09 kg/generation when body weights at birth,3 and 6 months were excluded and further decreased to 6.94 kg/generation when selection based on yearling weight only. From the practical stand point, selection on I 5 involving W9 can be considered as the best for improving W12 since its application is earlier, less expensive, higher accuracy than any index excluding W12 and giving reasonable amount (+5.39 kg) improvement in W12 as compared to direct selection (+6.94 kg).
Key words :Egyptian buffaloes, body weight, daily gain, phenotypic and genetic parameters, selection indexes and genetic gain.
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| Publication year |
2009
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| Pages |
89-100
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| Availability location |
معهد بحوث الانتاج الحيوانى شارع نادى الصيد- الدقى - الجيزة
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| Availability number |
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| Organization Name |
Animal Production Research Institute (APRI)
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| serial title |
Proc. of 2nd Animal Wealth Research Conf. in the Middle East &North Africa Cairo International Convention Center,Egypt,24 – 26 October
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| Author(s) from ARC |
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| External authors (outside ARC) |
كريمة عبد العزيز شاهين
جامعة عين شمس
عمر يسرى عبد الله
جامعة عين شمس
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| Agris Categories |
Animal husbandry
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AGROVOC
TERMS |
Body weight.
Breeding methods.
Genetic gain.
Phenotypes.
Water buffaloes.
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| Proposed Agrovoc |
Selection indexes;daily gain;
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| Publication Type |
Conference/Workshop
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