Effect of Arabinoxylan and Xylo-Oligosaccharide on Growth Performance and Intestinal Barrier Function in Weaned Piglets

SIMPLE SUMMARY: The study was conducted to explore effects of xylose with different polymerizations on growth performance, intestinal barrier function, and gut microbial composition in weaned piglets. Results showed that dietary supplementation of 1% xylo-oligosaccharide (XOS) or 1% arabinoxylan (AX) reduced diarrhea incidence of piglets compared with the control group (CON) but increased intestinal villus height, antioxidase activity, and sIgA contents (p < 0.05). With in vitro fermentation assay, XOS showed a sharper reduction of the pH curve than AX (p < 0.05). XOS increased the abundance of Lactobacillus and Bifidobacterium in the ileal digesta (p < 0.05), while AX increased the abundance of Bifidobacterium in the colonic digesta (p < 0.05). In conclusion, both XOS and AX improved the intestinal barrier function and reduced the diarrhea incidence of weaned piglets, and the XOS showed a faster microbial fermentation than the AX due to a lower polymerization and molecular mass. ABSTRACT: The purpose of this study was to explore the effects of xylose with different polymerizations on growth performance, intestinal barrier function, and gut microbial composition in weaned piglets. A total of 144 weaned piglets were assigned to 3 dietary treatments in a completely randomized design according to their body weight and sex. Dietary treatments included a corn-soybean meal basal diet (CON) and 2 additional diets formulated with 1% arabinoxylan (AX) and 1% xylo-oligosaccharide (XOS), respectively. Results showed that dietary supplementation of XOS or AX reduced diarrhea incidence of weaned piglets compared with the CON group (p < 0.05). XOS or AX increased the ileal villus height and intestinal activity of antioxidases in weaned piglets compared with the CON group (p < 0.05). XOS or AX reduced the ileal and colonic IL-6 content and increased the colonic sIgA and IL-10 concentrations in weaned piglets compared with the CON group (p < 0.05). XOS or AX increased the total organic acids concentrations in the ileum and in vitro fermentation (p < 0.05). XOS increased the abundance of Lactobacillus and Bifidobacterium in the ileal digesta (p < 0.05), while AX increased the population of Lactobacillus in the ileal digesta and the abundance of Bifidobacterium in the colonic digesta of weaned piglets (p < 0.05). In conclusion, both XOS and AX reduce diarrhea incidence and improve antioxidant capacity, immune function, and populations of beneficial bacteria, while microbial fermentation of XOS with a lower polymerization and molecular mass can produce more organic acids and an increased abundance of Lactobacillus and Bifidobacterium in the upper gut of weaned pigs compared with AX.