Ruminal characteristics, blood pH, blood urea nitrogen and nitrogen balance in Nili-Ravi buffalo (bubalus bubalis) bulls fed diets containing various level of ruminally degradable protein

Four ruminally cannulated Nili-Ravi buffalo bulls were used in a 4 x 4 Latin Square Design to determine the influence of varying level of ruminally degradable protein (RDP) on ruminal characteristics, blood pH, blood urea nitrogen (BUN) and nitrogen (N) balance. Four isonitrogenous and isocaloric diets were formulated (NRC, 2001). The control diet contained 50 % RDP. The medium (MRDP), high (HRDP) and very high (VHRDP) ruminally degradable protein diets had 66, 82 and 100 % RDP, respectively. Increasing the level of dietary RDP resulted in linear decrease in ruminal pH. Dietary RDP had a quadratic effect on total bacterial and protozoal count with maximum microbial count at 82 % RDP diet. Increasing dietary RDP resulted in linear increase in DM digestibility. Increasing the level of dietary RDP resulted in linear decrease in crude protein and neutral detergent fiber digestibilities. Blood pH remained unaltered across all diets. A linear increase in ruminal NH3-N and BUN was noticed due to increasing level of dietary RDP. A positive N balance was noticed across all experiment diets. The findings suggest that buffalo bulls can utilize up to 82 % RDP of total CP (16 %) with optimum results.