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Published on: September 20, 2021
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General and specific combining abilities for different economic traits in broiler chickens
C S Ooi1, T K Mukherjee, W C Wong
1Faculty of Agriculture and Division of Genetics, School of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia.
Summary
General combining ability (GCA) significantly impacts broiler traits like body weight and weight gain across breeds. Specific combining ability (SCA) also influences these traits, but not feed efficiency.
Area of Science:
- Animal Genetics
- Quantitative Genetics
- Poultry Science
Background:
- Broiler production relies on optimizing growth and feed efficiency.
- Understanding genetic variation in broiler breeds is crucial for selective breeding.
Purpose of the Study:
- To assess breed differences in combining abilities for broiler traits.
- To investigate genetic influences on body weight, weight gain, and feed efficiency.
Main Methods:
- A complete diallel cross of four broiler breeds was performed.
- Data from male and female birds were analyzed separately.
- Analysis focused on general combining ability (GCA), specific combining ability (SCA), and reciprocal effects (RE).
Main Results:
- GCA was the most significant source of variation for all traits in both sexes.
- SCA significantly affected body weight (both sexes) and weight gain (females).
- SCA did not influence feed efficiency, and reciprocal effects were minimal.
Conclusions:
- Broiler breed differences are largely explained by general combining ability.
- Specific combining ability plays a role in body weight and weight gain, but not feed efficiency.
- Genetic selection should prioritize GCA for improving broiler performance.
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