The objective of this study was to evaluate the influence of dietary supplementation of dried yeast culture and monensin sodium on digestion coefficients, some rumen fermentation, and some blood constituents' parameter in buffalo male calves. Eighteen (18) apparently healthy male buffalo calves (Bubalus bubalis) at 10-11 months of age with an average body live
weight (LBW) of 164.6±8.08 kg were selected randomly and divided into three similar groups according to their body weight (6 calves in each) with a completely randomized design. The control group fed the basal ration without any supplementation, the2nd group (YG) fed the basal ration supplemented with 15g/head/day dried yeast Saccharomy cescervisiae (“XP" Yeast Culture, Diamond V) while, the 3rd group (MG) fed basal ration supplemented with 1mg of monensin sodium /kg.b.wt/day for six months. Results revealed that, the DM intake kg/d and feeding values as (TDN and DCP) increase significantly (P<0.05) in buffalo calves fed (YG) and (MG) supplemented groups, MG group was the highest significantly (P<0.05) in average daily gain while, there was decreased insignificant differences in feed conversion of MG and YG groups respectively. Ruminal pH values showed limited change without any significantly affect while ruminal ammonia-N concentration, ruminal VFA's
proportion in propionate in MG group. Total VFA at 3hr post-feeding for yeast culture group (YG) recorded the highest significant (P<0.05) values. On the other hand, the values of ruminal butyrate decreased in MG group and ruminal propionate proportion in yeast group. The digestibility values of DM, CP and CF were higher (P<0.05) in MG and YG
supplemented groups. It was observed that fed MG group showed improved nutritive values as total digestible nutrients (TDN) and digestible crude protein (DCP) than control group (P<0.05). Glucose, globulin and urea concentrations of blood plasma were significantly differ (P<0.05), but the cholesterol, creatinine concentration and activity of ALT had little effects
due to yeast and monensin treatment effects. In conclusion, supplementation 1mg/kg.b.wt/day of monensin sodium and 15g/head/day yeast culture (Saccharomy cescervisiae) to diets of buffalo male calves had positive and beneficial effects on enhance digestion, nutritive values, rumen fermentation, blood constituents andenhancing daily weight gain consequently.