Detection of cytolethal distending toxin (cdt) genes of Campylobacter Jejuni and Coli in fecal samples of pet birds in Iran

Campylobacteriosis is one of the most common bacterial intestinal disorders of humans in many countries. A wide range of domestic and wild bird species have been identified as natural reservoirs. The aim of this study was to determine the Campylobacter spp from pet birds and screen the determined Campylobacters for presence of virulence cytolethal distending toxin (cdt) genes. A total of 660 fecal samples from 32 different species of pet birds were taken and examined for detection of Campylobacter spp. and were investigated for presence of cdt genes. All the samples were collected from clinically healthy birds that were kept in cage, zoological parks, and/ or in zoo of Tehran, the capital of Iran. In total, 20 thermophilic Campylobacter were detected from 8 different avian species. From 20 confirmed Campylobacter spp., 16 samples (80%) were C. jejuni positive and 4 (20%) were C. coli in species-specific PCR test. Furthermore, out of 20 detected Campylobacter, 13 (65%) harbored the various subunits of cdtA, cdtB and cdtC genes, and 7 (35%) were negative for all tested cdt genes. Our findings indicate that the carriage rate of Campylobacter in different species of cage and/or in zoo birds is high and confirm that cdt genes may frequently be present in campylobacter spp.