Feeding companion animals with high-protein diets has been a demand of the market and pet owners. However, the protein quality and quantity consumed can interfere with the amount of undigested protein that reaches the hindgut and be fermented. Intestinal fermentation can be desired when well controlled. This study tested two protein sources (hydrolyzed chicken liver and poultry byproduct meal) combined at three dietary protein concentrations (24, 32, and 40% crude protein on dry matter basis) and their effects on the apparent total tract digestibility (ATTD), fecal and urinary characteristics, and fecal metabolites of healthy adult dogs. In summary, diets containing higher inclusion of hydrolyzed chicken liver had improved protein ATTD. However, the same diets impaired the ATTD of fat and carbohydrates and decreased metabolizable energy. High-protein diets retained more water in the feces and increased the fecal output. Fecal consistency was affected, scored as soft and moist stools, but remained within an acceptable score. Dogs-fed poultry byproduct meal diets had greater concentrations of fecal protein fermentation metabolites, such as ammonia and branched-chain fatty acids, possibly related to a greater amount of undigested protein that reached the hindgut and was fermented.

Read the full article in the Journal of Animal Science.