0
Objective: The present study aims to evaluate the effects of varying dietary selenium-enriched yeast (SeY) levels on intestinal morphology, epithelial mucus production, antioxidant activity, and colonic bacterial communities in growing-finishing pigs.
Methods: Thirty 90 d-old growing-finishing pigs (54.37±2.13 kg) were randomly assigned to five treatment groups. The control group (CON) was fed a basal diet, while the other four groups were fed the basal diet supplemented with SeY at 0.3, 1, 3, and 5 mg/kg, respectively, for an 80-day of feeding trial. At the end of the experiment, pigs were euthanized, and samples from the jejunum, ileum, colon, and feces (day 52 and final day) were collected.
Results: The results showed that the addition of SeY at 0.3 mg/kg increased villus height, villus height/crypt ratio, and mucus production in the ileum, as evidenced by the increase in goblet cell number and mucus thickness. Furthermore, 0.3 mg/kg SeY up-regulated the mRNA expression levels of the MUC-1, claudin-1, occludin, and ZO-1 genes. In contrast, high-dose SeY at 5 mg/kg resulting in damage to mucosal morphology. Ileal antioxidant activity of SOD and GSH-Px, and jejunal mRNA expression of GPX-1 and GPX-4, were higher in response to SeY. Faecal Se excretion increased in SeY groups in a dose-dependent manner. SeY led to a significant difference in beta diversity among treatment groups and led to a significant decrease in the concentrations of isobutyric and isovaleric acids when compared to the control group. The acetate, propionate, butyrate, and total short-chain fatty acids were positively correlated with the biomarker genera Agathobacter (SeY at 0.3mg/kg), while isobutyrate and isovalerate were negatively correlated with biomarker genera Lactobacillus (SeY at 0.3mg/kg). Fecal accumulation of Se was positively correlated with the biomarker genera Alloprevotella (SeY at 3mg/kg) and Prevotellaceae_UCG-001 (SeY at 5mg/kg) and was negatively correlated with biomarker genera Agathobacter (SeY at 0.3mg/kg), Bacteroides (CON), and Faecalibacterium (CON).
Conclusion: SeY doses of 0.3 mg/kg have beneficial effects on intestinal health, whereas prolonged SeY doses up to 5 mg/kg may compromise the intestinal mucus function in growing-finishing pigs.
Su L, Yi H, Xu E, Xiao M, Gao Y. Colonic bacterial community responding to selenium-enriched yeast supplementation associated with improved gut mucus function in growing-finishing pigs. BMC microbiology. 2025; 25(1): 213. https://doi.org/10.1186/s12866-025-03909-5