Influence of Incorporating Different Levels of Solid State Fermented Biomass in Total Mixed Rations on In Vitro Digestibility and Methane Production

Abstract

The aim of this study was to evaluate the effect of incorporating different levels of solid state fermented (SSF) biomass on in vitro digestibility and methane (CH4) production. The total mixed rations (TMRs) were prepared using concentrates (40%), wheat straw (30%), groundnut straw (30%) and were used as substrate for in vitro studies. The SSF biomass was prepared using Aspergillus oryzae and Trichoderm areesei spp. of fungi. The SSF biomass having enzyme carboxymethyl cellulase having activity of 680 IU/g was incorporated in TMRs @ 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10% by replacing wheat straw on part basis. The in vitro apparent and true dry matter digestibility (DMD) of TMR increased with increasing levels of SSF biomass in the TMRs. The highest in vitro apparent and true DMD was found at inclusion of 5.0% SSF biomass which increased significantly (P<0.01) by 14.36 and 12.92%, respectively. Digestibility of OM increased significantly by 13.94% (P<0.01) as compared to control group. With increasing level of SSF biomass, in vitro CH4 production reduced as compared to control TMR and maximum reduction was observed at an inclusion level of 5.0% SSF level. In vitro CH4 production (mL/100 mg DM) reduced (P<0.01) by 16.91% than the value observed in control group. Methane production in terms of mL/100 mg apparent and true DMD reduced by 27.55 and 26.80%, respectively as compared to control group. Hence, solid state fermentation biomass improved digestibility and reduced methane production under in vitro conditions, however, in vivo studies are required for such confirmation.