Figure 5. Rarefaction curves of the alpha diversity indexes in different groups. Rarefaction curves of (A) the Chao1 index, (B) observed species index, (C) Shannon index, (D) Simpson index, (E) PD whole tree index, (F) goods coverage index of fecal samples from different groups. All of the alpha diversity indexes achieved stability in different groups, which means the sequencing sample size for gut microbiota analysis is sufficient and the sequencing depth is enough.