Silage fermentation and bacterial community of bur clover, annual ryegrass and their mixtures prepared with microbial inoculant and chemical additive

The objective of this study was to evaluate the silage fermentation and bacterial community of bur clover, annual ryegrass and their mixtures in south of China. Bur clover, annual ryegrass and their mixtures were ensiled without additive (control), or with lactic acid bacteria inoculant (LABi, 106 cfu/g of fresh weight) and formic acid (FA, 3 mL/kg of fresh weight) for 60 d of fermentation. Untreated bur clover displayed high bacterial diversity resulting in a poor fermentation. LABi and FA reduced bacterial diversity and enriched the relative abundance of Lactobacillus, Pediococcus or Sporolactobacillus species during ensiling, resulting in improved silage fermentation. Annual ryegrass contained relative abundance of Proteobacteria and Clostridium species, and produced more butyric acid. This study confirmed that LABi and FA could reduce microbial diversity and improve silage quality; and Clostridium species produced butyric acid which caused a poor fermentation.