Effect of supplementing herbal feed additives containing saponins to the total mixed ration on the enteric methane emission and nutrient utilization in buffalo calves

A 120 days growth study was conducted to assess the impact of dry extract of herbal feed additives (HFAs) containing saponins [Kulthi (Dolichos biflorus), patha (Cissampelos pareria) and shatavari (Asparagus racemosus)] supplemented at 2% of DM intake to total mixed ration (TMR) containing roughage to concentrate (R:C) ratio of 65:35 on enteric methane emission, nutrient utilization and performance of male Murrah buffalo calves. The supplementation of diet with HFAs did not affect the DM intake, digestibility of nutrients, N-retention and gain in weight. The ruminal ammonia concentration was depressed, while that of TCA-N in the SRL was improved (P<0.01) in animals fed TMR supplemented with shatavari. The acetate concentration in the rumen decreased (P<0.05) while that of propionate (P<0.05) and butyrate (P<0.01) increased, resulting in lower acetate to propionate ratio (P<0.01) in animals fed TMR supplemented with HFAs. The enteric methane emission was the lowest (P<0.01) in animals fed TMR supplemented with kulthi in comparison to control and other HFAs supplemented groups. The rumen metabolites, blood profile and excretion of purine derivatives were not affected by inclusion of any of the HFAs. It may be concluded that kulthi (Dolichos biflorus) supplemented at 2% to TMR containing R:C ratio of 65:35, mitigated enteric methane production significantly without affecting nutrient utilization, and performance of buffalo calves.