Fig. 6From: The gastrointestinal microbiome in dairy cattle is constrained by the deterministic driver of the region and the modified effect of dieta Principal coordinate analysis (PCoA) plot of the gene catalog at the genus level between the forage-based (F) and grain-based (G) diets in each gastrointestinal tract (GIT) region. The differences between groups were assessed using the ANOSIM test based on the Bray–Curtis dissimilarity index. b Comparison of alpha diversity (richness index) and beta diversity (Bray–Curtis) between the F- and G-fed animals, respectively. Significance is based on the relative index of each cohort according to the Wilcoxon rank-sum test. *p < 0.05, **p < 0.01, ***p < 0.001. c The different abundances in dominant taxa at the phylum and genus levels of the bacterial, archaeal, and eukaryotic communities among the GIT regions between the F and G diets. The number and top taxonomic populations of the significantly increased (d) and decreased (e) abundances of SGBs from the proximal to distal GIT (Wilcoxon rank-sum test, log2fold−change > 1 and p < 0.05). The height of the column represents the number of differential SGBs classified into specific genera. RUM, rumen; RET, reticulum; OMA, omasum; ABO, abomasum; DUO, duodenum; JEJ, jejunum; ILE, ileum; CEC, cecum; COL, colon; REC, rectumBack to article page