Genome-wide association study identifies variants associated with semen volume in white-feathered broilers.

Semen is a measure of the reproductive efficiency of roosters, which affects the economic benefits of white-feathered broilers. Over the years, research in this field has mainly focused on hens, while there have been fewer studies on the reproductive traits of roosters. To identify the genes related to the semen traits of roosters, we used a chicken 55 K SNP chip to genetically type the white-feathered population (220) and performed imputation with resequencing data from 97 roosters. In total, 1 048 576 SNPs were obtained and used for genome-wide association analysis of semen volume, from which 197 genome-wide significant markers were identified, all within the interval of 13.82-16.12 Mb on chromosome 7. By combining our results with the biological functions of genes in the interval, four candidate genes were identified that potentially relate to semen volume: FAPP1, OSBPL6, SESTD1 and SSFA2. Our findings may provide a basis for further research on the genetic mechanism and marker-assisted selection of semen volume in white-feathered broilers.