Human milk-derived Limosilactobacillus reuteri improved growth performance of weaned pigs by modulating systemic immune responses and enhancing intestinal health.

This study aimed to evaluate the effects of dietary supplementation of human milk-derived Limosilactobacillus reuteri (REU) on growth performance, frequency of diarrhea, and systemic and intestinal health parameters of weaned pigs. Dietary supplementation of REU had greater (P = 0.046) average daily gain during d 1 to 7 and d 15 to 28, and feed efficiency over the overall period (d 1 to 28). Pigs in REU group had tended to lower (P = 0.060) frequency of diarrhea than non-supplemented group. Pigs fed REU tended to have lower concentrations of serum cortisol (P = 0.061) and had lower interleukin-6 (P = 0.014), and tumor necrosis factor-α (P = 0.033) on d 7, and also had lower serum interleukin-6 (P = 0.027) and transforming growth factor-β1 (P = 0.008) levels on day 14 than those fed control diet. Probiotic REU had greater (P = 0.034) serum total protein levels on d 28 than non-probiotic diet. Pigs in REU group tended to have increased (P = 0.062) villus height in the ileum compared with those in control group. Pigs fed REU had upregulated claudin-1 (P = 0.002) and interferon-γ (P = 0.032) genes expression in the ileum than those fed control diet, but downregulated interleukin-8 (P = 0.004) gene expression. Dietary supplementation of human milk-derived REU improved growth performance of weaned pigs by modulating inflammatory responses and enhancing intestinal barrier integrity. These results suggest that the potential of human milk-derived probiotics as an effective strategy for improving growth performance and health in antibiotic-free swine production system.