| Titles |
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English :
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Estimation of heterosis and combing abilities for some economic traits in chickens
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Arabic :
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تقدير الخلط و قدرة التوافق لبعض الصفات الاقتصادية في الدواجن
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| Abstract |
Two exotic breeds of chickens namely New Hampshire (NH) and White Plymouth (WP) and two native breeds namely Dandarawi (DN) and Silver Montazah (SM) were used in diallel crossing experiment. this experiment was carried out at the Poultry Research station in EL-Qanater Animal Production Research Institute. Ministry of Agriculture, Egypt in the period from November 1985 to June 1986. A total of 2413 chicks were included in the present study to estimate heterosis, general (GCA) and specific (SCA) combining abilities, maternal ability (MA) and reciprocal or sex linked effects (SL) on body weights and measurements at different ages as well as carcass traits at 20 weeks of age. Phenotypic correlations between traits studied were also estimated.
Breed group was found to have a significant (P<0.001) source of variation on body weights, body measurements and carcass traits. Average of body weights, body measurements and carcass traits of crossbred chicks were generally higher than those of purebreds.
Estimates of heterosis for all traits showed that crossbreeding was Usually associated with an increase in most body weights and measurements and carcass traits studied. Significant differences were obtained among each crossbred and its reciprocal for most traits studied. The DNxNH crossbred chicks manifested the most superior percent of heterosis while the SMxNH crossbreds were the most inferior ones for body weights and measurements. The DNxSM crossbred chicks had the highest percent of heterosis while the WPxNH crossbreds recorded the lowest percent of heterosis for carcaaa traits. Crossing between local breeds gave the highest magnitude of heterosis for most traits followed by crossing between exotic breeds and finally by crossing of exotic breeds with local ones though it gave a relative high magnitude of heterosis.
Highly significant differences (P<0.01or 0.001) due to effects of hatch, sex and hatch x sex interaction for most traits studied were, obtained.
Sire-breed, dam-breed and sire-breed x dam-breed interaction contributed significantly in the variation of most traits studied. The DN sire were the best performing as a sire-breed followed by SM while WP dams were the best as a dam-breed followed by SM for most traits. Contributions of sire-breed in the variation averaged 13.5% for body weights, 11.2% for body measurements, 24.8% for carcass traits and 26.4% for non-edible carcass traits. While the contribution of dam -breed averaged 35.2% 30.1, 33.2% and 20.5% for these traits in the same order. Contributions of interaction between sire-breed and dam-breed in the variation averaged 50.0% for body weights, 30.1% for body measurements, 37.2% for carcass traits and 47.0% for non-edible carcass traits.
General (GCA) and specific (SCA) combining abilities and maternal ability (MA) affected significantly (P<0.0l) most traits studied. Non-significant differences due to reciprocal or sex linked effects (SL) were obtained for body weights and measurements of most ages, except for later ages (16 and 20 weeks). The DN breed had the highest estimates of GCA for most traits studied, followed by SM, while WP breed had the highest estimates of MA. Crossbreds of NHxDN and SMxWP had the highest estimates of SCA for all traits. Crossbreds of NHxSM, DNxNH, WPxSM, NHxWP DNxWP had positive estimates of SL for most traits studied.
Phenotypic correlations among body weights, body measurements and carcass traits were positive (P<0.01) and high in magnitude for most cases. Estimates ranged between 0.42 and 0.91 among body weights; 0.46 and 0.91 among body measurements; 0.61 and 0.91 between body weights and measurements; 0.31 and 0.99 among carcass traits.
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| Publication year |
1990
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| Pages |
PP. 141
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| Availability location |
مكتبة معهد بحوث الانتاج الحيوانى- شارع نادى الصيد- الدقى - الجيزة
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| Availability number |
349
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| Organization Name |
Animal Production Research Institute (APRI)
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| Country |
Egypt
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| Author(s) from ARC |
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| Agris Categories |
Animal husbandry
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AGROVOC
TERMS |
Body measurements.
Body weight.
Carcass composition.
Chickens.
Crossbreeding.
Economics.
Heterosis.
Performance testing.
Phenotypes.
Postweaning period.
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| Publication Type |
Master Thesis
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