Dietary Supplementation With Yeast Cell Wall Modulates Gut Microbiota and <scp>SCFAs</scp> Production to Improve Intestinal Health in Adult Cats

Yeast cell wall (YCW) has shown several probiotic activities, including modifying intestinal flora structure, decreasing the abundance of pathogenic bacteria, and regulating intestinal morphology. However, the effect of dietary addition of YCW on intestinal health in cats has not been fully studied. In this study, 20 healthy adult cats were split into a control group (CON) and a YCW addition group (YCW) for a 42-day trial. On Day 21 of the experiment, the fecal Calprotectin level in the YCW group was significantly lower than that in the control group (<i>p</i> < 0.05). By measuring the content of short-chain fatty acids (SCFAs), we found that YCW supplementation elevated the propionate level in cats' feces (<i>p</i> < 0.05). On Day 42 of the experiment, the serum levels of interleukin-1β (IL-1β) and diamine oxidase (DAO), as well as the fecal level of Calprotectin, were markedly declined in the YCW group when compared to the control group (<i>p</i> < 0.05). We further discovered that the YCW treatment significantly enriched several intestinal beneficial genera in cats, such as Bacteroidaceae, Ruminococcaceae, <i>Blautia</i>, and <i>Lachnoclostridium</i> (<i>p</i> < 0.05). Additionally, cats in the YCW group showed higher levels of acetate and propionate (<i>p</i> < 0.05). This study suggested that ingestion of YCW could relieve intestinal inflammation and enhance intestinal barrier function in cats, which may be related to its capacity to enhance the gut microbiota composition and the SCFAs concentrations.