Molecular characterization of the cloacal microbiota of wild and captive parrots

Abstract

The gastrointestinal microbiota plays a fundamental role in health and disease. Only limited data are available about the composition of the intestinal microbiota of captive animals compared to those of wild animals. The aim of the present study was to characterize the cloacal microbiota of apparently healthy wild and captive parrots. A total of 16 parrots, 8 wild and 8 captive, belonging to 3 different species, were used in this study. Cloacal material was collected via cloacal swabbing. DNA was extracted and 16S rRNA genes were amplified using universal bacterial primers. Constructed 16S rRNA gene clone libraries were compared between groups. A total of 518 clones were analyzed, and 49 operational taxonomic units (OTUs) were identified. The OTUs were classified in 4 bacterial phyla: Firmicutes (72.9%), Proteobacteria (14.9%), Actinobacteria (12%), and Bacteroidetes (0.2%). Bacterial diversity was significantly lower in wild birds than in captive birds. Principal component analysis based on the Unifrac distance metric indicated that the cloacal microbiota differed between wild and captive parrots. Staphylococcus saprophyticus was significantly more abundant in wild birds, while Escherichia coli was significantly more abundant in captive birds. In conclusion, wild and captive parrots appear to have differences in the composition of their cloacal bacterial microbiota. The clinical significance of these differences remains to be determined.