Effects of different combination ratios of paper mulberry and alfalfa on rumen bacterial diversity in Angus cows

Rumen fluid was collected from two ruminally fistulated Angus cows aged 20 to 24 months. Using 16S rRNA sequencing technology, the effects of mixed in vitro fermentation of alfalfa and paper mulberry at different ratios on rumen bacterial diversity were studied. According to the mass ratio, the experimental materials were divided into five treatment groups: 0∶1 (DA), 1∶3 (D3A1P), 1∶1 (D1A1P), 3∶1 (D1A3P), and 1∶0 (DPM). Rumen fluid was collected for detection, and bacterial diversity was analyzed after fermentation for 96 hours. Shannon and Simpon α-diversity index was not significantly different across the five groups (P > 0.05). Chao1 indices of D1A3P, D3A1P, and D1A1P were significantly higher than those of DA and DPM (P < 0.05). ACE index of D1A3P was significantly higher than that of the other groups (P < 0.05). Community structure analysis showed that the dominant phyla were Firmicutes, Bacteroidetes, Proteobacteria, Euryarchaeota, and Spirochaetes. The relative abundance of Firmicutes in DA, D1A1P, and DPM was significantly higher than that in the other two groups (P < 0.05). The relative abundance of Proteobacteria in D1A3P was significantly higher than that in the other groups (P < 0.05). The relative abundance of Euryarchaeota in D3A1P was significantly higher than that in the other groups (P < 0.05). At the genus level, the relative abundance of unidentified Bacteroidales in D1A1P was significantly higher than that in the other groups (P < 0.05). The relative abundance of Sutterella and Succiniclasticum in DPM was significantly higher than that in the other groups (P < 0.05). At the phylum and genus levels, the relative abundance of bacterial in the rumen changed with differing ratios of alfalfa and paper mulberry.