Genomic selection for two traits in a maternal pig breeding scheme

Area of Science:

• Animal Breeding and Genetics
• Quantitative Genetics
• Livestock Improvement

Background:

• Conventional pig breeding schemes balance production and maternal traits.
• Genomic selection offers potential improvements over traditional methods.
• Optimizing genomic selection implementation is crucial for maximizing genetic gain.

Purpose of the Study:

• To compare various genomic selection strategies against a conventional pig breeding scheme.
• To evaluate the impact of genomic selection on genetic gain and inbreeding rates.
• To determine the optimal allocation of genotyping resources for improved breeding outcomes.

Main Methods:

• Simulation of a nucleus pig breeding population (Norwegian Landrace model).
• Implementation of genomic selection with varying genotyping strategies for boars and females.
• Assessment of total genetic gain, rate of inbreeding, and trait contribution.

Main Results:

• Genotyping boars at selection increased genetic gain by 13% and reduced inbreeding by 40%.
• Genotyping 2,400 females annually increased maternal trait contribution to genetic gain from 16% to 32%.
• Pre-selecting males via genotyping improved genetic gain by 5-11% compared to post-boar test genotyping.

Conclusions:

• Genotyping females is prioritized over additional males for increasing maternal traits and reducing inbreeding.
• Genomic selection effectively enhances genetic gain and manages inbreeding in pig populations.
• Strategic genotyping of females is key for maximizing genetic progress in maternal traits.