Effect of solid-state fermentation by oyster mushroom (Pleurotus florida) on nutritive value of some agro by-products

The present research aims to investigate the effect of Pleurotus florida fungi cultivation on chemical composition, gas production characteristics, organic matter digestibility (OMD), metabolizable energy (ME), net energy lactation (NEL) and short-chain fatty acid (SCFA) of some agro by-products (rice straw, wheat straw, barley straw, soybean straw, canola straw, pea straw and rice husk). Dry matter, organic matter and neutral detergent fibre were significantly decreased upon with fungi application in all treatments (p < 0.01). Fungal treatment did not cause significant difference in the amount of acid detergent fibre (ADF) in soybean straw, canola straw, pea straw and rice husk (p > 0.05), but significantly decreased ADF in rice straw, wheat straw and barley straw (p < 0.05). In experimental treatments, fungi cultivation did not vary significantly in acid detergent lignin and ether extract content (p > 0.05). Processing significantly increased ash and crude protein in all treatments (p < 0.01). The amount of gas production was not significantly affected by fungi cultivation in wheat straw, soybean straw, canola straw and rice husk; however, it was significantly increased upon processing in rice straw, barley straw and pea straw (p < 0.05). The amount of OMD in rice husk was not changed significantly, but processing significantly increased OMD in other treatments (p < 0.05). Fungi cultivation significantly improved ME in all treatments (p < 0.05). The amounts of NEL and SCFA were significantly increased with treatment by fungi (except rice husk) in all substrate (p < 0.01). The results of this study generally indicated that nutritive value of agro by-products was improved upon fungal treatment.