Gallic acid influencing fermentation quality, nitrogen distribution and bacterial community of high-moisture mulberry leaves and stylo silage

To investigate the feasibility of vegetal gallic acid (GA) improving silage quality, fermentation parameter, nitrogen distribution and bacterial community of mulberry leaves and stylo ensiled with 1% and 2% GA were analyzed after 60-d fermentation. The results showed that GA addition decreased dry matter loss (6.08% vs 5.35%, 17.79% vs 11.56% in mulberry leaves and style silage, respectively), pH (6.51 vs 5.98, 5.55 vs 4.57), butyric acid (0.41% and 0.83% DM, undetected in GA groups) and ammonia-N (0.71% vs 0.19%, 1.46% vs 0.29% TN) contents and increased lactic acid (2.27% vs 6.68%, 0.91% vs 1.91% DM) and acetic acid (1.68% vs 3.20%, 0.97% vs 2.02% DM) contents. Meanwhile, the relative abundance of Clostridium or Enterobacter was decreased, and that of lactate-producing bacteria was increased in mulberry leaves and stylo silage. In conclusion, GA could be used as a green additive to improve fermentation quality and protein preservation during ensiling.