Effects of whole-plant corn and hairy vetch (Vicia villosa Roth) mixture on silage quality and microbial communities.

ABSTRACT

OBJECTIVE: Hairy vetch is considered to improve the nutritional value of corn because of its high protein and mineral levels. To better understand the mechanism underlying hairy vetch regulated whole-plant corn silage fermentation, this experiment investigated the fermentation quality and bacterial community of whole-plant corn and hairy vetch mixture. METHODS: Whole-plant corn and hairy vetch were mixed at ratios of 100 (Mix 100), 82 (Mix 82), 64 (Mix 64), 46 (Mix 46), 28 (Mix 28), and 010 (Mix 010) on a fresh weight basis. After ensiling 60 days, samples were collected to examine the fermentation dynamics, ensiling characteristics, and bacterial communities. RESULTS: Mix 010, Mix 28, and Mix 46 showed poor fermentation characteristics. Mix 82 and Mix 64 silages showed high quality, based on the low pH, acetic acid, and ammonia nitrogen levels and the high lactic acid, crude protein, and crude fat contents. The bacterial diversity was affected by the mixing ratio of the two forage species. The genus Lactobacillus dominated the bacterial community in Mix 100 silage, whereas with the addition of hairy vetch, the relative abundance of unclassified-Enterobacter increased from 7.67% to 41.84%, and the abundance of Lactobacillus decreased from 50.66% to 13.76%. CONCLUSION: The silage quality of whole-plant corn can be improved with inclusion levels of hairy vetch from 20% to 40%.