Effect of sialyllactose administration on growth performance and intestinal epithelium development in suckling piglets

Sialyllactose (SL) is an abundant carbohydrate in sow’s colostrum, but decreases during the first few days of lactation. Here, we investigated its effect on growth performance and intestinal epithelium development in pigs during the suckling period. Sixteen litters of suckling piglets were divided into two groups (Control and SL group). All piglets were breast fed and the SL group was orally administrated with 4 g SL per day for 21 d. Results showed that SL administration increased the litter weight (P = 0.043) and tended to elevate the average body weight (P = 0.084) at weaning. The serum concentrations of immunoglobulin G and glutathione peroxidase were elevated, but the concentrations of tumor necrosis factor α, malondialdehyde, and diamine oxidase were decreased upon SL administration (P < 0.05). Moreover, SL administration elevated the villus height, the ratio of villus height to crypt depth, and the activities of lactase and sucrase in jejunum (P < 0.05), and decreased the total apoptotic cells in ileal epithelium (P = 0.003). The expression levels of tight-junction protein ZO-1 in the jejunum and ileum, and critical functional genes such as the glucose transporter 2, divalent metal transporter 1, and insulin growth factor 1 receptor in the jejunum were elevated by SL supplementation (P < 0.05). Importantly, SL increased butyric acid concentration, and elevated the abundances of Lactobacillus and Bifidobacterium in cecum (P < 0.05). These results suggest that SL could improve the growth performance of suckling piglets, which was associated with improved immunity and antioxidant capacity, as well as the intestinal barrier functions.