Prevalence of Campylobacter jejuni, Campylobacter coli and enteric Helicobacter in domestic and free living birds in North-Western Italy

In order to investigate the prevalence of some thermophilic Campylobacter (C. jejuni and C. coli) and enteric Helicobacter (H. pullorum and H. canadensis) in domestic and wild birds, a total of 278 bird caecal samples were analyzed over a 2 year period in North-Western Italy. Samples were collected from poultry raised in intensive farming at the slaughterhouse (n = 102, group A) and in small scale rural farms (n = 60, group B) as well as from wild birds (n 116, group C). PCR amplifications were carried out on DNA extracted from caecal samples. Molecular assays targeted the hipO gene for C. jejuni, the asp gene for C. coli and the 16S rRNA gene of H. pullorum/H. canadensis. To differentiate H. pullorum from H. canadensis, PCR products were subjected to an ApaLI digestion assay. Prevalence of thermophilic Campylobacter and enteric Helicobacter was significantly different among groups (p < 0.0001). Campylobacter infections were detected in all three bird groups (78.4% group A, 18.3% group B and 38.8% group C, respectively), Helicobacter infections were only detected in poultry, with H. pullorum infecting 68.6% of group A and 21.7% of group B birds. H. canadensis was detected in Guinea fowls (group A) and for the first time in pheasants (group B). Mixed infections by enteric Campylobacter and Helicobacter were shown in 53.9% of group A and in 5.0% of group B. Our results show that both microorganisms commonly infect poultry, especially intensive farming animals. Only hooded crows among the wild bird group (group C), proved to be highly sensitive to Campylobacter infection.