PCoA plot of the microbiota from birds fed a control or resin acids-supplemented diet. Principle coordinate analysis (PCoA) plot of Bray–Curtis dissimilarities. Each point represents a single chicken microbiome. Significant separation of ileal microbial communities were revealed using ANOSIM (p = 0.002). This difference was less pronounced in the caecal microbiota (p = 0.055).