摘要：Background and Objective: Utilization of plantation waste, such as palm stems, is still limited due to its high lignin content and low digestibility. Therefore, it is necessary to apply technology to improve feed quality in terms of both nutritional value and waste digestibility. Such technology will ultimately improve the quality of animal feed. White rot fungi, such as the basidiomycete Pleurotus ostreatus ( P. ostreatus ), can degrade lignin by using lignases, which include lignin peroxidase, manganese peroxidase and laccase. Materials and Methods: The study was conducted in the Nutrition Laboratory of Andalas University. This study used completely randomized design with factorial pattern. Factor A is P. ostreatus dose (3, 5 and 7%) and factor B is the fermentation time (1, 2 and 3 months). Results: The results showed that fermentation of palm stem with P. ostreatus for 3 months could decrease NDF content up to 11.03%, ADF content up to 9.65%, hemicellulose content up to 1.39% and lignin content up to 7.24%. Conclusion: The dose of P. ostreatus and the fermentation time did not interact significantly. However, the fermentation time of 3 months significantly (p<0.05) decreased the contents of NDF, ADF, hemicellulose and lignin in palm midribs and can be used to improve the quality of animal feed ingredients, especially feed used for ruminants.
