Dietary lysolecithin supplementation improves growth performance of weaned piglets via improving nutrients absorption, lipid metabolism and redox status.

Lysolecithin is widely used as emulsifier to improve the digestibility and retention of fat. The current study aimed to investigate the effects of dietary lysolecithin supplementation on growth performance, nutrients absorption, lipid metabolism and redox status of weaned pigs. A total of 60 weaned piglets were assigned into two dietary treatments in a randomized complete block design, receiving basal diet with 0 or 1000 mg/kg lysolecithin for a period of 28 days. Each dietary treatment had 10 replicates with 3 piglets per replicate. Growth performance and faecal score were monitored during trial. Samples of blood, ileum and liver tissues were collected and analyzed for serology, intestinal histomorphology and lipid metabolism-related gene and protein expressions. Dietary lysolecithin supplementation increased average daily gain (+15%, P < 0.05) and tended to increase average daily feed intake (+14%, P = 0.08) in overall experimental period. At final, the average body weight of piglets in lysolecithin group was 10% greater than that of control group (P = 0.09). In addition, dietary lysolecithin supplementation improved ability of nutrients absorption as indicated by the higher D-xylose level in plasma (P < 0.05). Moreover, piglets from lysolecithin group had higher concentration of high-density lipoprotein (P < 0.05), but lower triglyceride (P < 0.05) in plasma. The inclusion of lysolecithin in diet increased the level of reduced glutathione (GSH) and GSH to oxidized glutathione (GSSG) ratio in plasma and liver (P < 0.05), but attenuated the levels of malondialdehyde and GSSG in ileum (P < 0.05). The up-regulation of lipogenesis-related genes (FAS and ACC) and down-regulation of lipolysis (PNPLA2 and PABP1) and lipid-mobilization (PGC-1α and SRIT1) genes were observed in lysolecithin relative to control piglets. Compared with control group, dietary lysolecithin supplementation up-regulated protein expressions of GPX4, SREBP1 and LPL in liver and LPL in ileum (P < 0.05). Collectively, our study indicates that dietary lysolecithin supplementation improved growth performance of weaned piglets, which may be associated with the improved nutrients absorption, redox status and lipid metabolism.