Conversion of sorghum stover into animal feed with white-rot fungi: Pleurotus ostreatus and Pleurotus pulmonarius

Treatment of crop residues with some species of white-rot fungi can enhance the nutritive value. After the fungal treatment of sorghum (Sorghum bicolor) stover with two white-rot fungi in a solid state fermentation, the chemical composition and in vitro digestibility of the resultant substrate was determined. The results show a significant (p < 0.05) increase in crude protein contents from 2.54% for the control to 4.51% for Pleurotus ostreatus (POS) and 4.59% for Pleurotus sajor pulmonarius (PPT). The nitrogen free extract (NFE) content also increased significantly (p < 0.05). The crude fibre decreased significantly from 31.65% for the control to 27.49% for POS and 23.54% for PPS. There were also consistent significant decreases (p < 0.05) in the values obtained for NDF, ADF ADL. Significant differences were also observed in the hemicellulose and cellulose contents. Fermentation of the insoluble fraction (b) was enhanced by the fungal treatment. Wide variations were also observed in the mineral contents of the different substrates The estimated organic matter digestibility (OMD) ranged from 42.99 to 57.75%, short chain fatty acid ranged from 0.56 to 0.94 ìM and metabolisable energy (ME) ranged from 5.97 to 8.21 MJ/Kg DM. This result suggests that fungal treatment of sorghum stover resulted in improved CP and digestibility, hence its potential in ruminant nutrition.