August 03, 2020

Interpretive Summary: Dried yeast positively affect microbial composition in dogs

Interpretive Summary: Dried yeast cell walls high in beta-glucan and mannan-oligosaccharides positively affect microbial composition and activity in the canine gastrointestinal tract in vitro

By: Anne Wallace

The gut microbiome is a diverse ecosystem of bacteria, yeasts and viruses which reside throughout the intestines of larger organisms, influencing health, digestion and metabolism. The specific populations of microbes within these communities are affected by both intrinsic and extrinsic factors, such as genetics and diet, respectively.

Prebiotics are the indigestible components of food, usually dietary fibers, that feed beneficial microbes within the gut microbiome. Mannan-oligosaccharides (MOS) and β-glucans are two such prebiotics. In this June 2020 Journal of Animal Science study, researchers evaluated the effects of MOS and β-glucans derived from the yeast Saccharomyces cerevisiae for potential health benefits, in dogs.

The in vitro Simulator of the Canine Intestinal Microbial Ecosystem (SCIME) system was set-up to model the intestinal microbiota of dogs. Mannan-oligosaccharides and β-glucans from a S. cerevisiae-based yeast product was evaluated in three increasing doses (0.5, 1.0, and 2.0 g/d). Results found that short-chain fatty acids – beneficial fermentation byproducts produced by gut microbes – increased as the dose of the yeast product increased. Populations of microbes within the families Enterobacteriaceae and the Fusobacteriaceae, which contain opportunistic pathobionts, also decreased with increasing S. cerevisiae-based yeast product.

Overall, the results of this study support the authors’ hypothesis that MOS and β-glucans would alter gut microbiome composition and have potential health benefits for dogs, in a simulated environment. Future studies looking at the effects of MOS and β-glucans both separately and synergistically, in an in vitro and in vivo study may be justified.