Application of optimal contribution selection, trait distribution management, and group selection in layer chickens

Area of Science:

• Animal Breeding and Genetics
• Quantitative Genetics
• Poultry Science

Background:

• Optimal Contribution Selection (OCS) balances genetic gain and inbreeding.
• Poultry data with 7 generations of pedigree and 18 traits were analyzed.
• Current inbreeding rates are low, limiting reduction without impacting genetic gain.

Purpose of the Study:

• Evaluate the impact of OCS, trait management, and group mating on poultry breeding.
• Assess strategies for maximizing long-term response to selection.
• Investigate methods to balance genetic gain and inbreeding rate.

Main Methods:

• Applied OCS, trait management, and group mating to real White Leghorn poultry data.
• Utilized estimated breeding values (EBV) for 18 traits.
• Incorporated flexible mating ratios and predicted progeny trait distribution management.

Main Results:

• Flexible mating ratios increased genetic gain by 5.3-23.8% and reduced genetic diversity loss compared to fixed ratios.
• Trait management achieved market-specific egg weight EBV differences without compromising multi-trait index or parental coancestry.
• Multi-sire mating strategies showed minimal impact on predicted progeny index, parental coancestry, and inbreeding.

Conclusions:

• Multi-generation simulations are needed for long-term impact assessment of OCS.
• Real-world implementation scenarios are crucial for decision-making in breeding programs.
• The studied selection and mating strategies are applicable to other species' breeding programs.