Solid-state fermentation with Pleurotus ostreatus improves the nutritive value of corn stover-kudzu biomass.

A batch culture technique was used to evaluate dry matter (DM) digestibility of corn stover (Zea mays L.) and kudzu, Pueraria montana (Lour.) Merr. after solid-state fermentation (SSF) with a white-rot fungus, Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm. Five dietary treatments consisting of mixtures of corn stover (C) and kudzu (K) in varying ratios, (1) 100C:0K, (2) 75C:25K, (3) 50C:50K, (4) 25C:75K, and (5) 0C:100K, were inoculated with P. ostreatus (MBFBL 400) and subjected to SSF for 0, 35, and 77 days. The study was arranged as a 5 × 3 factorial design with 3 replicates. Grass hay was included in the study as a control. Interactions (P < 0.05) between treatments and fermentation time were noted for the fermentation kinetics. Asymptotic gas was the highest (P < 0.05) for 0C:100K and 100C:0K on day 77. Treatment effect (P < 0.001) and treatment × fermentation time interaction (P < 0.001) were noted for in vitro dry matter digestibility (IVDMD). On day 77, treatment 4 had the highest (P < 0.001) IVDMD value, while treatment 1 had the lowest (P < 0.001) IVDMD. There was no difference (P > 0.05) between treatments 3, 5, and control. Numerically, the ranking of their IVDMD values from the highest to the lowest is 4 > 2 > 5 > control >3 > 1. The results show that the treated corn stover and kudzu mixes were comparable with the control, which is good quality hay. This is the first report that demonstrates the potential use of a combined mixture of corn stover and kudzu in ruminant animal feed development.