| Titles |
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English :
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Genetic and phenotypic parameters of some longevity and lifetime production traits in holstein-friesian cows raised in Egypt
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Arabic :
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المقاييس الوراثية و المظهرية لبعض صفات طول الحياة و الكفاءة الانتاجية لماشية الهولستين- فريزيان المرباة في مصر
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| Abstract |
Heritability estimates of longevity traits [number of lactations completed during the cow's life (LNO), its herd life (HL), and its productive life (PL)], and lifetime production traits [total milk yield (L TMY) and lifetime lactation period (LLP)] were estimated using 5642 records for 887 cows, daughters of 94 Holstein bulls, using the mixed model and multi-trait animal model. Also, genetic and phenotypic correlation coefficients among all these traits were calculated.
Heritability estimates of longevity traits ranged from 0.04 to 0.06, while were 0.15 and 0.05 for LTMY and LLP. respectively. Longevity traits had high genetic correlation >98) and was 0.96 between LLP and LTMY. Genetic correlations between each of longevity traits and L TMY ranged from 0.85 to 0.90. Phenotypic correlations were less than the corresponding genetic correlations among most traits. These correlations ranged from 0.84 to 1.0 among longevity traits, from 0.53 to 0.62 among longevity traits arid LTMY, from 0.48 to 0.68 between LLP and longevity traits while it was 0.90 between LLP and LTMY.
Product-moment correlation among longevity traits ranged from 0.983 to 0.999 and was 0.974 between lifetime total milk yield and lifetime lactation period. The product- moment correlations between lifetime lactation period and longevity traits ranged from 0.442 to 0.740. The same trend was observed for the corresponding rank correlations but with relatively lower estimates:
Key words: Genetic parameters, longevity, lifetime production, HolsteinFriesian, Egypt.
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| Publication year |
2004
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| Pages |
53-60
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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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| Country |
Egypt
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| City |
Moshtohor
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| serial title |
Annals of Agricultural Science
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| Volume |
42
. 1
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| Department |
Cattle Breeding Research Department
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| Author(s) from ARC |
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| External authors (outside ARC) |
ماهر حسب النبى خليل
جامعة الملك سعود
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| Agris Categories |
Animal husbandry
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AGROVOC
TERMS |
Cows.
Egypt.
Genetic parameters.
Longevity.
Phenotypes.
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| Proposed Agrovoc |
lifetime production;
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| Publication Type |
Journal
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