Fig. 2

Relative abundance of the main gut bacterial groups. a At the phylum level. b At the genus level. On d7 and d14, gut microbiota were generally dominated by the phyla Proteobacteria and Firmicutes, followed by Actinobacteria and Bacteroidetes. At the genus level, Klebsiella and Escherichia-Shigella were dominant. On d14, bacteria such as Bacteroides, Staphylococcus, Clostridium_sensu_stricto_1, Parabacteroides, and Bifidobacterium were more abundant than on d7