Fig. 4

PCoA plots based on Bray–Curtis dissimilarity matrix showing beta diversity at ASV level. Bacterial community structures (beta diversity) in the digesta of the fish, a Not subjected to antibiotic treatment (nonmedicated group) and b Subjected to antibiotic treatment (medicated group). The whole bacterial community of each sample is represented by a dot in the figure. Samples with similar bacterial compositions are close to each other. See Fig. 1 legend for description of the diet groups and sampling time points