Fermentação ruminal de ovinos alimentados com alto concentrado e grãos de girassol ou gordura protegida Ruminal fermentation of sheep fed high-concentrated diet containing sunflower grains or protected fat

Abstract

Seis ovinos machos, não castrados, da raça Santa Inês, com média de peso de 30kg, fistulados no rúmen, foram distribuídos em delineamento de quadrado-latino duplo (3x3). Três períodos e três dietas, uma controle, sem inclusão de fonte de lipídio, e duas com inclusão de grãos de girassol ou gordura protegida, foram testados quanto aos parâmetros ruminais. Foram verificadas diferenças (PSix 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.

Keywords

• ovino
• ácidos graxos de cadeia curta
• amônia
• bactérias ruminais
• lipídios
• sheep
• short-chain fatty acids
• ammonia
• ruminal bacteria
• lipids