Fig. 2

Metagenomic KEGG and COG pathway map and metabolomics data analysis. The different colors in the figure represent different pathways, and the size of the color blocks in the figure represents the average abundance (A). Metagenomic COG pathway map. The different colors in the figure represent different pathways, and the size of the color blocks in the figure represents the average abundance (B). PCA analysis of HRFI and LRFI duck metabolites (C). HRFI and LRFI ducks metabolites expression. A curated list of 922 metabolites of the cecum were analyzed the associated with possible effects on feed intake genes were labeled on the plot. Two vertical lines indicate gene expression fold change (HRFI vs. LRFI) > 1.2 and < − 1.2, respectively, and the horizontal line indicates the adjusted P value (FDR q-value) of 0.05. P values were calculated by two-sided Wilcoxon rank-sum test. The color of the dot represents the FDR (q-value) levels (D)