Figure 2.

Abundance and diversity of intestinal flora. (a) Rarefaction curves of three groups for species number after 80000 random sequences number. The curve in each group was near smooth when the sequencing data were great enough with few new species undetected. ((b) and (c)) Box plot of difference among groups of Chao 1 index (used to assess abundance) and Shannon index (used to assess diversity). P values were from Wilcoxon rank sum test. (d) Principal Component Analysis (PCA) of three groups based on Euclidean distances. The percentage of PC1 and PC2 represented the contribution value of the first and second principal components to the sample difference.