The inclusion of yeast in pet food can provide health benefits and increase palatability. Corn-fermented protein is a co-product from ethanol production which contains approximately 20% to 25% yeast. In this work, 11 cats were fed diets containing no yeast (CON) and either 3.5% brewer’s dried yeast (BDY), 2.5% brewer’s dried yeast plus 17.5% distillers dried grains with solubles (BDY+DDGS), or 17.5% corn fermented protein (CFP). Cats were fed each dietary treatment for 14 d with a 9-d adaptation phase followed by a 5-d total fecal collection. Processing parameters, kibble characteristics, stool quality, nutrient digestibility, and palatability were analyzed. Processing parameters needed to be adjusted for CFP to result in a similar bulk density to BDY. The CFP resulted in harder and tougher kibble compared to BDY. The total fecal output and fecal score of cats were similar for BDY and CFP. However, nutrient digestibility was lower for CFP compared to BDY, likely due to the increase in dietary fiber. Short-chain and branched-chain fatty acid concentrations in fecal samples were not altered among diets. The palatability of BDY appeared to be greater than CFP for cats. Further research is needed to evaluate the possible impact of yeast in CFP on animal health.

Read the full article in the Journal of Animal Science.