Describing feed efficiency using metabolomic data in pigs

Feed conversion ratio (FCR) is commonly used to determine production efficiency in pigs. However, the basic biological mechanisms of this complex trait are still largely unexplored. In this study, we aimed to describe FCR in Italian Large White pigs using metabolomic data. For 691 pigs, FCR random residuals (FCR-RR), untargeted plasma metabolomic data (constituted by about 1000 metabolites) and high-density single nucleotide polymorphisms were available. We first identified two extreme groups of pigs (100 with the lowest and 100 the highest FCR-RR) and compared their metabolomic data using Sparse Partial Least Squares Discriminant Analysis and Boruta algorithm. With the combination of these two approaches, we identified 12 metabolites that could discriminate the two extreme groups of pigs. These metabolites were involved in a few metabolomic pathways, including fatty acid oxidation, carnitine, alanine, and histidine metabolism. Genomic heritability of the selected metabolites ranged from 0.11 to 0.35. The obtained results can contribute to identify molecular proxies useful to describe feed efficiency and develop new breeding strategies in pigs. Acknowledgments: This study has received funding from the European Union – NextGenerationEU under the National Recovery and Resilience Plan (PNRR) – FEEDTHEPIG, proposal code P2022FZMJ9 – CUP J53D23018310001 and from the European Union’s Horizon Europe research and innovation programme under the grant agreement No. 01059609 (Re-Livestock).