RAMA PRASAD, J (Major)KRISHNA MOHAN, D.V.GPARTHASARATHY, MSATYANARAYANA REDDY, P.V.VSARJAN RAO, KSRINIVAS KUMAR, D2016-12-222016-12-222009-05http://krishikosh.egranth.ac.in/handle/1/92069ABSTRACT: Experiments were carried out on young graded Murrah buffalo bulls, lactating graded Murrah buffaloes and graded Murrah buffalo bull calves to study the effect of feeding diets supplemented with or without thermo tolerant probiotic (Levucell SC 20) on voluntary feed intake, rumen fermentation pattern, nutrient digestibility, milk production and composition and on growth performance. The voluntary DM intake expressed as kg/day or as kg/100 kg. b.wt. or as g/kg w0.75 was marginally higher in buffalo bulls fed with probiotic supplemented diet as compared with the control. The rumen fermentation studies with fistulated young buffalo bulls revealed that all the nitrogen fractions of rumen fluid, pH and TVFA increased marginally while NH3-N concentration of rumen liquor increased significantly (P<0.05) in the buffalo bull calves fed diet supplemented with probiotic as compared with the control. All nitrogen fractions except residual nitrogen and TVFA peaked at 4 h post feeding. Peak rumen pH values were recorded immediately after feeding (0 h) while residual N values peaked at 2 h post feeding. The protozoal count (P<0.05) and total bacterial count (P<0.01) increased significantly with probiotic supplementation in the diet compared with the control. The protozoal and total bacterial counts were also peaked at 4 h post feeding. The DM intake (kg/day) was higher in the probiotic supplemented group of buffalo bull calves in growth study as compared with the control. The average digestibility coefficients (%) of DM, EE, and NDF (P<0.05), OM, CP, CF, ADF and cellulose (P<0.01) increased significantly with probiotic supplementation in the diet of buffalo bull calves as compared with the control animals. However, the average digestibility coefficients (%) of NFE and hemicellulose did not differ significantly between the two groups. All the buffalo bull calves were in positive N, Ca and P balances. The DCP (P<0.01) and TDN (P<0.05) intakes (kg) increased significantly with probiotic supplementation in the diet as compared with the control. The ADG was significantly (P<0.05) higher in the probiotic supplemented diet (549.91 g/d) as compared with the control (462.13 g/d). Feed efficiency (kg feed/kg gain) and cost of feed per kg gain were 9.94 vs. 9.52 and Rs. 33.10 vs. Rs. 32.01 in the control and treatment groups, respectively. The dry matter intake (kg/day) increased marginally in the probiotic supplemented group of lactating buffaloes as compared with the control. The average digestibility coefficients (%) of all nutrients were higher in lactating buffaloes fed probiotic supplemented diet as compared with the control. The DCP and TDN contents were higher in the probiotic supplemented group as compared with the control. The average milk yield, butter fat yield, 6% FCM, SNF per cent and total solids were higher in buffaloes fed diets supplemented with thermo tolerant probiotic as compared with the control. However, the differences between the two groups were not significant. The feed efficiency was improved and cost of feed per kg 6% FCM yield was decreased marginally (Rs 8.06 vs. Rs. 8.44) with probiotic supplementation in the diet of lactating buffaloes as compared to the control. It can be concluded from the present results that supplementation of thermo tolerant probiotic (Levucell SC 20) in the diets of buffalo bull calves increased the growth rate, improved feed efficiency and decreased feed cost/ kg gain as compared to the control. However, it was observed that the recommended dose of probiotic (0.5 g /head/day) supplemented in the diet of lactating buffaloes may be little to demonstrate significant positive response on milk yield and milk composition.enThesis