Effect of different opening times on methanogenic potential of different fermentation types of silage during feed-out stage

Aerobic deterioration of silage material is unavoidable during the feed-out stage; therefore, in this study, the influence of the feed-out stage on the methanogenic potential of different silage fermentation types was evaluated. Lactic acid in corn straw silage was the first substance to be completely consumed by 3 days after opening and the pH increased substantially. In homolactic fermentation, yeast and mold proliferated in an aerobic environment; the organic dry matter loss rate was less than 2.0% and cumulative methane yield_orig reduction rate was only 3.9% at 1 day after opening than silage storage. However, these values increased to 18.9% and 34.9%, respectively, 3 days after opening, which were much higher than those obtained under non-homolactic fermentation. Therefore, a feed-out frequency of no more than one day is recommended in practical engineering applications. Meanwhile, promoting non-homolactic fermentation can improve the aerobic stability of raw materials and reduce energy loss.