Effects of Edible Mushroom Cultivation on Fiber Degradation and Feed Quality of Highland Barley Straw

This study used highland barley straw from the Tibetan Plateau to cultivate Pleurotus ostreatus, Pholiota nameko, Lentinula edodes, Pleurotus eryngii, and Hericium erinaceus, addressing straw waste, forage shortages, and underutilized barley straw. The results showed that highland barley straw was suitable for cultivating P. ostreatus and P. nameko, with P. ostreatus yielding significantly more. After fruiting, spent mushroom substrates (SMS) from both species had higher crude protein, fat, and ash, with reduced fiber content compared to raw straw. P. ostreatus SMS showed greater protein accumulation and fiber degradation, offering better feed quality than P. nameko. Fungal communities were more concentrated under P. ostreatus, while P. nameko had higher diversity. Multivariate analyses showed that fungal community structure correlated with protein, fat, and feed quality, while bacterial communities were linked to fiber content. Functional predictions indicated that P. ostreatus enriched carbohydrate and energy metabolism pathways, while P. nameko was more associated with biosynthetic functions. Overall, cultivating mushrooms on barley straw improved SMS feed quality, with P. ostreatus showing greater potential for feed use.