Six not castrated Santa Inês breed male sheep, weighing 30kg, fistulated in the rumen, were randomly alloted in a double Latin-Square design (3x3). Three periods and three diets, a control without addition of the lipid source, and two with addition of sunflower seeds or protected fat, were tested on the ruminal fermentation. Differences (P<0.05) between diets for ruminal ammonia concentration (18mg/dL) were observed. However, effects were not detected on pH (6.1); the total production of short-chain fatty acids (98mM); proportions of acetate (66.4%), propionate (20%), and butyrate (13%); and acetate:propionate ratio (3.2:1). The solid-adherent bacteria isolated from the rumen content of animals fed control diet had higher nitrogen content (10.7%) than those fed protected fat diet (9.8%) or sunflower seeds diet (9.1%). The production of nitrogen by bacteria attached to solid-control diet (170mg/kg) did not differ from sunflower seeds (153mg/kg) or protected fat diets (160mg/kg). The inclusion of sunflower seeds or protected fat in diets with high concentrate for sheep provided suitable environment for rumen fermentation.
sheep; short-chain fatty acids; ammonia; ruminal bacteria; lipids
