Abstract
In livestock, many economically important traits vary among breeds and lines, reflecting the influence of different genetic backgrounds on trait expression. In this study, we assessed how molecular phenotypes vary among three heavy pig breeds, by analysing the level of more than 180 plasma metabolites using a targeted metabolomic platform. Plasma was from 12 Italian Large White, 12 Italian Duroc and 12 Italian Landrace pigs, raised and fed in the same way. Advanced data analysis methods, including the Boruta algorithm and random forest, were employed to compare plasma profiles in the three breeds. The level of 11, 14 and five metabolites differed between Italian Duroc and Italian Large White breeds, Italian Duroc and Italian Landrace breeds and Italian Large White and Italian Landrace breeds, respectively. Distinct breed-related metabolic profiles emerged, aligning with known characteristics of the breeds. Specifically, Italian Duroc pigs are marked by diminished biogenic amine levels, Italian Large White pigs by lower sphingomyelin levels, and Italian Landrace by elevated acylcarnitine and phosphatidylcholine levels. These results suggest potential differences in breed-related energy and lipid metabolism strategies. These findings could be used to develop new molecular phenotypes useful in pig breeding and selection and to explore breed-precision feeding strategies.