Pig farming is an activity of great relevance for the Brazilian economy and worldwide food security. Feed efficiency, which is defined as the ability of animals to convert feed into performance outputs (e.g., body weight in pigs), is directly related to the long-term sustainability of the pig industry due to its impact on production costs and the environmental footprints of the industry. Therefore, selective breeding for improved feed efficiency has been a primary goal in the pig industry. In this context, we aimed to identify and validate candidate genes associated with 2 feed efficiency traits in pigs, i.e., feed conversion ratio (FCR) and residual feed intake (RFI). We first performed a systematic review to gather published results of genome-wide association studies for FCR and RFI in worldwide pig populations. Subsequently, we identified candidate genes associated with FCR and RFI based on the most significant single nucleotide polymorphism (SNP) markers. Our results highlight the genes MED18, PHACTR4, ABCC2, TRHDE, FRS2, FAR2, and FIS1 as strong candidates for FCR, and ADGRL2, ASGR1, ASGR2, and MAN2B1 for RFI. These findings contribute to a better understanding of the genetic mechanisms associated with feed efficiency traits in pigs, providing a foundation for future improvements in pig breeding programs.

Read the full article in the Journal of Animal Science.