Genetic correlation between boars, barrows and gilts for various carcass traits.

Area of Science:

• Animal breeding and genetics
• Swine production
• Quantitative genetics

Background:

• Understanding genetic correlations between sexes is crucial for effective swine breeding programs.
• Genotype-by-sex interactions can influence selection response for carcass traits.

Purpose of the Study:

• To estimate genetic correlations for carcass traits in Lacombe and Yorkshire swine breeds.
• To determine the existence and impact of genotype-by-sex interactions.
• To assess the necessity of sex-specific genetic parameters in selection equations.

Main Methods:

• Analysis of 11 generations of selection study data.
• Estimation of genetic correlations between boars, gilts, and barrows for various carcass traits.
• Statistical evaluation for genotype-by-sex interactions.

Main Results:

• Genotype-by-sex interactions were identified for total carcass fat, ham lean area, and ham lean percentage, all normalized by cold carcass weight.
• No significant genotype-by-sex interactions were found for carcass length, longissimus muscle area, ham percentage, or ham lean percentage.
• Selection using pooled genetic parameters across sexes was more advantageous than using sex-specific parameters.

Conclusions:

• While some carcass traits exhibit genotype-by-sex interactions, pooled genetic parameters offer a robust approach for selection in swine.
• Separate genetic parameters for boars and gilts are not consistently necessary for optimizing selection response.
• The findings support using unified genetic parameters for broader selection efficiency in swine breeding.