FIG 4.

Sex differences in antibiotic effects on the gut microbiota at the phylum level in healthy mice. (A and B) Changes in the observed species and Shannon index in mice after antibiotic exposures. (C) Relative abundance of the microbial composition after antibiotic exposure. A classification based on PCA was performed using the gut microbiome in male (D) and female (E) mice. (F and G) Changes in abundances of Firmicutes and Proteobacteria in mice after antibiotic exposure. The interaction effect between sex and antibiotic on microbes was evaluated by a linear mixed-model, and pairwise multiple comparisons were analyzed using Student's t test with a Bonferroni adjustment. NAbx, no antibiotic exposure; Vanc, vancomycin; CiMe, ciprofloxacin and metronidazole; M, male; F, female. Significance level: ****, P < 0.0001.