Effect of Rumen Modifier on Methanogenesis and Feed Digestibility under in Vitro Conditions

Neem seed cake (Azadirachta indica), mahua seed cake (Madhuca longifolia), fennel seed (Foeniculum vulgare), harad (Terminalia chebula), fruit pulp of bahera (Terminalia bellirica), fruit pulp of fruit of amla (Phyllanthus emblica) and ajwain seed (Trachyspermum ammi) were dried, powdered and mixed in a ratio of 2: 2: 2: 1: 1: 1: 1 to prepare a mixture of rumen modifier-7 (RM-7) and was tested at 0 (control) 5, 10, 15 and 20% of the substrate along with 0.06% of sodium sulphate (except control) to study their effects on rumen fermentation in vitro. Inclusion of RM-7 at 5, 10, 15 and 20% of substrate along with 0.06% of sodium sulphate did not affect gas production but there was significant (P<0.01) reduction (18.5 and 34.1%) in methane production as well as feed digestibility (60.88 to 52.71%)). Total volatile fatty acids (VFA), individual VFA (acetate, propionate and butyrate) and ammonia N levels were not affected by any of the treatments. Hence, inclusion of rumen modifier (RM-7 at 5, 10, 15 and 20% + 0.06% sodium sulphate of substrate) did not affect total gas production but there was significant reduction in methane production upto 10% level.