148 Dietary gestational and lactational live yeast supplementation to sows impacts milk and colostrum proteome profiles and piglet gut development.

Abstract Sow milk serves as the sole source of nutrients, immune-stimulating and growth-promoting factors for suckling piglets. Milk composition and production are largely affected by sow nutrition during gestation and lactation. Due to the dependence of piglets on milk, the suckling period presents a critical opportunity for maternal nutritional intervention to support piglet intestinal development. This study investigated the effects of live yeast (LY, Saccharomyces cerevisiae) supplementation to sows during late gestation and lactation on intestinal development of piglets, and the proteome profiles of sow colostrum and milk. On d 77 of gestation, 40 sows were allotted to each of two dietary treatments: without (CON) or with (LY) live yeast supplementation at 0.05% of diet during gestation and 0.1% during lactation. Colostrum and milk samples were collected on d 0, 10, and 18 of the lactation (n = 6). Intestinal tissue samples were collected from one piglet per litter on postnatal days (PND) 0, 10, 18, and postweaning days (PWD) 7 and 14 (n = 10). Results showed that maternal LY supplementation increased mRNA expression of interleukin (IL)-6 on PND18 and IL-1β on PWD14 in the ileal mucosa (P < 0.05), with a trend towards higher IL-10 expression on PND18 in the ileal mucosa (P = 0.08). Additionally, LY piglets had increased mRNA expression of superoxide dismutase 1 (SOD1) in the ileal mucosa on PND10 and PWD14 (P < 0.05). Compared to CON piglets, LY piglets had increased protein abundance of E-cadherin on PWD7 and PWD14 in the jejunal mucosa (P < 0.05), with a tendency for greater E-cadherin on PND0 (P = 0.09). The LY piglets had a higher protein abundance of occludin and claudin-4 in the jejunal mucosa on PWD14 (P < 0.05). Shotgun proteomic analysis revealed a higher abundance of immune-associated proteins, including Ig-like domain-containing protein and complement proteins (Complement C8 alpha chain and C1q domain-containing proteins) in the colostrum, and IgG heavy chain in d 10 milk of LY sows than CON sows, whereas the abundance of prostaglandin synthetase was greater in d 10 milk of CON sows than LY sows (P < 0.05). Additionally, milk fat globule EGF and factor V/VIII domain containing protein and Niemann-Pick C2 were found to be more abundant in both d 10 and d 18 milk of LY sows (P < 0.05). In conclusion, dietary live yeast supplementation to sows during gestation and lactation enhanced piglet intestinal development by increasing immune-related proteins in colostrum and proteins involved in lipid uptake and processing in mature milk, thereby supporting neonatal immune and tissue development at different growth stages.