Figure 9 Volcano plot for statistical analysis of fecal differential metabolites. Note: Each point in the volcano plot represents a metabolite, the abscissa represents the multiple change of the group compared with each substance, the ordinate represents theP -value of the t-test , and the size of the scatter represents the VIP value of the OPLS-DA model. The blue dots in the figure represent the down regulated differential expression metabolites, the red dots represent the up regulated differential expression metabolites, and the gray dots represent the detected but not significantly different metabolites. In addition, the top 5 qualitative metabolites are selected and marked in the figure after sorting by P value.