Influence of biologically treated wheat straw diet on in vitro rumen fermentation, methanogenesis and digestibility

The present study was conducted to assess the nutritive worth of diets comprising of wheat straw (T1 diet) and basidiomycetes white-rot fungal (WRF) isolate RCK-SC treated wheat straw (T2 diet) for in vitro gas production, digestibility and rumen fermentation parameters. Diets (on dry basis) containing 70% straw, 10% berseem green forage, 17% groundnut cake, 2% mineral mixture and 1% salt were formulated. It was observed that in vitro total gas (GV 24 h), true DM and OM digestibility (48 h), in vitro NDF digestibility (48 h), microbial biomass production (MBP) and short chain fatty acid (SCFA) production were significantly (P < 0.05) higher in T2 diet to the extent of 9.71, 17.39, 14.92, 17.45, 6.34, 9.34%, respectively when compared to T1. While, total N and NH3-N in rumen liquor of both the diet remained same. Volatile fatty acids like propionate concentration increased (P < 0.05) with a decrease in acetate to propionate ratio (A:P). Methane production expressed as L/kg IVTDMD was significantly (P < 0.05) lower (13.86%) in T2 diet. This study demonstrates that fungal treatment of wheat straw using basidiomycetes WRF isolate RCK-SC produces better quality straw and its incorporation benefits rumen fermentation in vitro.