Fig. 4

Co-occurrence network and data association analysis. The co-occurrence network among caecum bacteria and metabolites in ducks with high and low feed residual intake. Relationships between caecum genus level top30 abundance microbial, significantly different top10 microbial functions and 5 differential metabolites related to fat metabolism. Blue edges indicate positive relationships, and red edges indicate negative relationships (A). Correlation Analysis between Microbial Community Levels and Metabolic Products in the Cecum. We ranked the microorganisms at the phylum level from small to large, selected the top 10 phylum level bacteria with 17 differential metabolic products, and performed correlation analysis between the top 10 abundance of species level and the top 50. B. trehalosi, which showed significant differences between the two groups. The bubble chart was plotted using the calculated log2 fold change (HRFI vs. LRFI) and p values. The size of the bubble indicates the statistical difference, with larger bubbles indicating more significant correlations. The color of the bubble represents the positive or negative correlation between the microorganisms and differential metabolic products. Orange represents positive correlation, while green represents negative correlation (B)