Fig. 4

Functional prediction of the gut mucosa microbiota of D. vulgaris from the three regions. Boxplots representing the Hellinger transformed abundances of the KEGG metabolic pathways differently abundant in the gut microbiota of D. vulgaris from the three regions (BA in pink, CR in violet and BO in orange) according to the Kruskal–Wallis test. The metabolic pathways reported in this figure are included in the macro functional categories of: A carbohydrate metabolism; B metabolism of cofactors and vitamins; C xenobiotics metabolism and biodegradation. The P value of significant pairwise differences between regions (according to Dunn’s pairwise test) is reported over the boxplots