Effects of Protein Supply from Soyhulls and Wheat Bran on Ruminal Metabolism, Nutrient Digestion and Ruminal and Omasal Concentrations of Soluble Non-ammonia Nitrogen of Steers

Three beef steers fitted with permanent cannulae in the rumen and duodenum were used to determine the effects of protein supply from soyhulls (SH) and wheat bran (WB) on ruminal metabolism, blood metabolites, nitrogen metabolism, nutrient digestion and concentrations of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). In a 3×3 Latin square design, steers were offered rice straw and concentrates formulated either without (control) or with two brans to increase crude protein (CP) level (9 vs. 11% dietary DM for control and bran-based diets, respectively). The brans used were SH and WB that had similar CP contents but different ruminal CP degradability (52 vs. 80% CP for SH and WB, respectively) for evaluating the effects of protein degradability. Ruminal ammonia concentrations were higher for bran diets (p 20%). (Key Words : Soyhulls, Wheat Bran, Soluble non- ammonia Nitrogen, Omasal Digesta, Nutrient Digestion)