Effect of AMC water on the diversity and composition of gut microbiota in MS piglets under weaning stress. (A) The rarefaction curve in bacterial communities based on the Shannon index. Each sample was shown by different line colors. (B-C) Bacterial alpha diversity based on (B) Chao 1 index and (C) Shannon index (_7d/_15d, 7 days/15 days after weaning). (D) Scatterplot from Principal Coordinates Analysis (PCoA) in bacterial communities based on the weighted UniFrac distance. (E) Microbial communities bar plot at the phylum level. (F) The ratio of Firmicutes/Bacteroidets. (G) Microbial communities bar plot at the genus level. (H) The changes of Lactobacillus abundance. (I) Microbial communities bar plot at the species level. (J) The changes of helveticus abundance. Statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc pairwise comparison. Data are presented as the mean ± SD. ns, not significant, *P < 0.05, **P < 0.01, and ***P < 0.001.