Diet digestibility and palatability and intestinal fermentative products in dogs fed yeast extract

This study aimed to evaluate the effects of yeast extract on the apparent total tract digestibility (ATTD) of nutrients, metabolisable energy (ME), and palatability of diet, and on intestinal fermentative products in dogs. In addition, we also evaluated the ATTD and ME of yeast extract in dogs. Four diets containing 0, 40, 80, and 120 g/kg of yeast extract were evaluated. Diet digestibility, faecal characteristics, and intestinal fermentative products were evaluated in 12 adult Beagle dogs distributed in a randomised block design, with two periods of 10 days each. Yeast extract digestibility was obtained by regression analysis. Sixteen adult dogs were used for the palatability test to compare the diets: 0 vs. 40 g/kg yeast extract. The yeast extract presented ATTD of dry matter = 77.3%, crude protein (CP) = 55.7%, acid-hydrolysed ether extract (AHEE) = 73.8%, and ME = 4947.3 kcal/kg. There was a linear reduction in ATTD of CP and AHEE in the diets with yeast extract inclusion (p <.05). There was a linear increase in faecal concentration of total short-chain fatty acids (SCFA) and a linear reduction in faecal pH with the dietary inclusion of yeast extract (p <.05). Dogs preferred the 40 g/kg over the 0 g/kg yeast extract diet (p <.001). The dietary inclusion of up to 120 g/kg yeast extract led to lower ATTD of CP and AHEE, and higher faecal concentration of SCFA. Furthermore, a diet with yeast extract was more palatable to dogs.