Fig. 7

The diversity and composition of the ileal microbiota in healthy and NE-infected chickens supplemented with DCA or butyrate. Day-of-hatch male Cobb broilers were supplemented with or without 1 g/kg NaB, 0.75 g/kg DCA (DCA1), 1.5 g/kg DCA (DCA2), or a mixture of 1 g/kg NaB and 0.75 g/kg DCA (NaB + DCA1) or 1 g/kg NaB and 1.5 g/kg DCA (NaB + DCA2). Six groups of animals were subjected to NE, while the remaining group was mock-infected. The proximal ileal digesta were randomly collected from 12 surviving animals/group on d 17 and subjected to 16S rRNA gene sequencing. Observed ASVs (A), Pielou’s evenness index (B), and Shannon index (C) were estimated and visualized using box and whisker plots. Significance was measured using the Kruskal–Wallis test and post hoc pairwise Wilcoxon rank-sum test. Different superscripts denote significance (P < 0.05) in pairwise comparisons. Principal coordinates analysis (PCoA) plots of weighted (D) and unweighted UniFrac distances (E). Significance was determined using PERMANOVA. Relative abundances of the top 15 families (F), top 15 genera (G), and top 20 ASVs (H) in the ileal microbiota are shown