Genome-wide association studies for feed efficiency, production and feeding behaviour traits in Canadian purebred Duroc pigs

Lay Summary The pork industry is a prominent contributor to the Canadian economy and food security by providing large quantities of pork and meeting high consumer demands. Feed efficiency is defined as the ability to convert feed into production outputs (e.g. body weight) and is highly emphasized during selection as it directly impacts production costs and sustainability. Likewise, production traits are also highly valued while feeding behaviour can provide valuable indirect indication of feed efficiency through low to moderate phenotypic and genotypic correlations. In this paper, we aimed to explore the genetic architecture behind feed efficiency, production and feeding behaviour traits through a genome-wide association study and identify key candidate genes. Many traits across these three categories were found to have similar genetic associations with strong shared signals detected on chromosomes 7 and 10. Additionally, genes such as PACSIN1, PTCH1, ADIPOR1 and ITPR3 were identified as novel candidate genes for backfat thickness, daily feed intake, feed conversion ratio, residual feed intake, residual gain, and residual intake and gain, suggesting that these traits may share a common genetic foundation. These results ultimately provide a genetic and biological basis for improving selection programs for economically important traits in Canadian Duroc pigs.