Marker-assisted selection based on a multi-trait economic index in chicken: Experimental results and simulation

Area of Science:

• Animal Breeding and Genetics
• Quantitative Genetics
• Genomic Selection

Background:

• Traditional breeding programs face challenges in simultaneously selecting for multiple production traits.
• Economic values of traits are crucial for optimizing breeding goals but are complex to integrate.
• Marker-assisted selection (MAS) offers potential for enhancing selection accuracy and efficiency.

Purpose of the Study:

• To develop and evaluate a novel method for simultaneous selection of multiple production traits using economic values and DNA markers.
• To assess the accuracy and effectiveness of the proposed economic index-marker assisted selection (EI-MAS) method.

Main Methods:

• Developed EI-MAS, integrating marginal economic values into a selection index based on predicted breeding values (BV).
• Utilized DNA marker information associated with quantitative trait loci (QTL) for BV prediction.
• Validated the method using real bird data and extensive simulation analyses.

Main Results:

• Real bird data showed significant correlations between sire progeny performance and expected performance (r = 0.61-0.76).
• Simulation indicated EI-MAS offers substantial advantages for low heritability traits.
• Selection response increased with more markers, wider marker distribution (10 cM), and larger progeny numbers (approx. 150).

Conclusions:

• EI-MAS provides an effective strategy for simultaneous selection of multiple production traits in animal breeding.
• The method's efficiency is influenced by marker density, distribution, heritability, and progeny size.
• EI-MAS holds promise for accelerating genetic gain in livestock populations.