Effects of Combinations of Goat Milk and Oligosaccharides on Altering the Microbiota, Immune Responses, and Short Chain Fatty Acid Levels in the Small Intestines of Mice

Goat milk and oligosaccharides play important roles in gastrointestinal health. A combination of goat milk with three oligosaccharides, stachyose (STS), fructo-oligosaccharide (FOS), and a prebiotics mixture (FGS), was fed to mice. Changes and functions of the microbiota, short chain fatty acid (SCFA) concentrations, and immune gene expression in the small intestines were determined. The FOS treatment increased the beneficial bacteria Lactobacillus and Bifidobacterium, the FGS treatment helped stabilize the microbial community, and the STS treatment significantly enhanced microbial diversity and the growth of Bacteroidetes. The oligosaccharide treatments regulated the gene expression levels of the immune factors tumor necrosis factor alpha (Tnfα), granzyme B (Gzmb), perforin (Prf), and aryl hydrocarbon receptor (Ahr). Stachyose significantly increased the concentrations of acetate and propionate compared with other treatments. These findings demonstrate that STS is the preferred carbon source for microbiota, slightly modulates SCFA production, and results in low immunogenicity in the small intestines of mice.