Moringa oleifera leaf polysaccharide regulates fecal microbiota and colonic transcriptome in calves.

This study investigated the effects of Moringa oleifera polysaccharide on growth performance indicators, serum biochemical indicators, immune organ indicators, colonic morphology, colonic microbiomics and colonic transcriptomics in newborn calves. 21 newborn calves were randomly divided into three groups of 7 calves per treatment group: control group (no Moringa oleifera polysaccharide addition); low-dose group (Moringa oleifera polysaccharide 0.5 g/kg); and high-dose group (Moringa oleifera polysaccharide 1 g/kg). This trial used gavage to feed MOP to calves. The test lasted 8 weeks. Calves were humanely electroshocked on the last day of the trial and slaughtered afterwards. Thymus, spleen, blood and colonic contents were collected for further testing. The results of this trial showed that MOP significantly increased the body weight of newborn calves and reduced the rate of calf diarrhea, thus promoting calf growth. Fecal scores showed a linear decrease with the addition of MOP. In terms of serum biochemistry, feeding MOP significantly increased serum ALB levels in a linear fashion. In terms of serum antioxidants, feeding MOP linearly increased CAT and T-AOC levels and decreased MDA concentrations, and in terms of serum immunity, feeding MOP linearly increased IgA, IgG, and IgM levels. At the same time, MOP regulated the abundance of Firmicutes and Bacteroidetes in the intestinal tract of calves, which reduced the occurrence of diarrhea. In addition, moringa polysaccharide could regulate genes related to inflammatory signaling pathways such as MAPK signaling pathway, TGF-beta signaling pathway, PI3K-Akt signaling pathway and TNF signaling pathway in calves' intestine to reduce the occurrence of intestinal inflammation. In conclusion, MOP can be used as a novel ruminant additive for the prevention of enteritis in calves.