Biodegradation of Leguminous Husks into High Protein Feed Products Using Oyster Mushrooms (Pleurotus ostreatus)

Background and Objective: High cost of conventional feedstuff is a major constraint to commercial livestock production in Nigeria. Leguminous crop residues which are abundant and cheap can fill the gap but are of very low nutrient quality. This study investigated the effect of P. ostreatus on three leguminous residues namely, groundnut shell (GS), cowpea husk (CH) and bambara nut shells (BS) with sawdust (SD) as the control. Materials and Methods: The 500 g of the different moist substrates which had been previously dried and milled into smaller particle sizes of at least 2 mm in diameter, were inoculated with 10 g of P. ostreatus spawn which were covered with transparent cellophane bags and placed in a dark room for 5 weeks to allow optimum conditions for colonization of the substrate. The samples were replicated 3 times. Subsequently, samples from each replicate were bulked, oven-dried and milled for chemical analysis. Results: The proximate analysis before and after the treatment showed an increase in nutrient quality parameters, crude fibre 42.05 vs 30.95%, 42.45 vs 37.90%, 52.32 vs 28.8%, 68.35 vs 59.5% for (GS), (CH), (BS) and (SD), respectively, crude protein 9.24 vs 18.08. 9.45% vs, 14.18, 9.30 vs 11.03% and 1.93 vs 2.63% for (GS), (CH), (BS) and (SD), respectively, ash content 10.60 vs 8.30%, 7.80 vs 12.56%, 10.90 vs and 13.50%, 0.5 vs 1.5% for (GS), (CH), (BS) and (SD), respectively, fat and oil 12.26 vs 1.90%, 5.70 vs 18.52%, 3.78 vs 3.78% and 7.04 vs 1.88% for (GS), (CH), (BS) and (SD), respectively. Conclusion: The mushroom variety Pleurotus ostreatus, could be used to enhance the nutritive quality of the crop residues under study.