Effects of culture length of Pleurotus eryngii grown on sugarcane bagasse on in vitro digestibility and chemical composition

Pleurotus eryngii was cultivated on sugarcane bagasse substrate to enhance the digestibility of bagasse. Effects of culture length on the digestibility and chemical composition were determined. Substrate consisting of bagasse and rice bran was incubated at 24 °C for 35 days under semi-anaerobic conditions then transferred to an incubation room at 17 °C to enable the fruit-bodies to emerge. The average yield of the fruit-bodies at the first flush was 74.3 g/culture bottle. The proportion of residual weight of dry matter in the substrate decreased by 0.242 on day 95, and further by 0.053 between days 95 and 155. The proportion of residual weight of lignin decreased by 0.350 on day 95, and further by 0.066 between days 95 and 155. The in vitro organic matter (OM) digestibility (IVOMD) of the substrate increased from 0.537 on day 0 to 0.693 on day 95. The in vitro digestibility of neutral detergent fiber excluded ash (IVNDFomD) increased from 0.480 to 0.584. The cumulative in vitro gas production (IVGP) for 48 h increased from 144 to 197 ml/g OM. Since there were no differences in IVOMD, IVNDFomD and IVGP between days 95 and 155, it was concluded that 95 days after inoculation was an appropriate culture length, at which spent bagasse substrate could be used as feed for ruminants.