Describing backfat and Semimembranosus muscle fatty acid variability in heavy pigs: Analysis of non–genetic factors

This study aimed to describe the multivariate structure of Semimembranosus muscle and backfat fatty acid (FA) composition in 798 Italian Large White heavy pigs and to investigate the effects of environmental factors and carcass characteristics on FA variations. The total FA variability in muscle and backfat was characterized by a negative correlation between saturated and polyunsaturated FAs, which strongly depended on the carcass adiposity. Slaughtering season was also relevant, with pigs slaughtered in autumn having more n-6 FAs and eicosadienoic acid in backfat, while pigs slaughtered in winter displayed more saturated FAs. Regarding Semimembranosus muscle, pigs with heavier belly cuts and slaughtered in autumn had higher proportions of cis-vaccenic and palmitoleic acids, while those slaughtered in summer had more saturated FAs. Slaughtering season emerged as a relevant factor shaping both backfat and muscle FA composition, indicating that more studies and attention should be paid to environmental factors, which may have effects on FA metabolism and deposition in finishing pigs.