Overview of Ecology and Aspects of Antibiotic Resistance in Campylobacter spp. Isolated from Free-Grazing Chicken Tissues in Rural Households

Argyrios Dermatas; Georgios Rozos; Konstantinos Zaralis; Aikaterini Dadamogia; Konstantina Fotou; Eugenia Bezirtzoglou; Konstantoula Akrida-Demertzi; Panagiotis Demertzis; Chrysoula Chrysa Voidarou

doi:10.3390/microorganisms12020368

Overview of Ecology and Aspects of Antibiotic Resistance in Campylobacter spp. Isolated from Free-Grazing Chicken Tissues in Rural Households

Microorganisms. 2024 Feb 10;12(2):368. doi: 10.3390/microorganisms12020368.

Authors

Argyrios Dermatas¹, Georgios Rozos^{2

3}, Konstantinos Zaralis³, Aikaterini Dadamogia², Konstantina Fotou², Eugenia Bezirtzoglou⁴, Konstantoula Akrida-Demertzi¹, Panagiotis Demertzis¹, Chrysoula Chrysa Voidarou²

Affiliations

¹ Food Chemistry Laboratory, Section of Industrial and Food Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece.
² Laboratory of Animal Health, Food Hygiene and Quality, Department of Agriculture, University of Ioannina, 47132 Arta, Greece.
³ Department of Agriculture, School of Agricultural Sciences, University of Western Macedonia, 53100 Florina, Greece.
⁴ Laboratory of Hygiene and Environmental Protection, Faculty of Medicine, Democritus University of Thrace, 68100 Alexandroupolis, Greece.

Abstract

Rural households all over the world rear backyard chicken mainly for their own consumption and, to a lesser extent, for barter trade. These chickens represent a staple dish with numerous culinary variations and a cheap source of protein. Although some Campylobacter species, and particularly Campylobacter jejuni and Campylobacter coli, have been associated with industrial poultry carcasses, studies concerning the ecology of this genus in rural households do not exist. To assess the prevalence of Campylobacter species in the tissues of backyard chickens, samples were collected from birds Gallus domesticus bred in households in the rural area of Epirus (Greece), and Campylobacter strains were isolated by quantitative methods at 37 °C and 42 °C. In total, 256 strains were identified, belonging to 17 Campylobacter species, with C. jejuni and C. coli being the most prevalent. From the four ecological parameters studied (size of the flock, presence of small ruminants in the same household, presence of other poultry species in the same household, and feeding leftovers of the household), the size of the flock and the presence of small ruminants and/or pigs in the same household mostly affected the distribution of these strains. To study the phenotypical resistance against 14 antibiotics, 215 strains were selected. The results showed a high prevalence of multidrug-resistance (MDR) strains extending to all classes of antibiotics. Further genome analysis revealed the presence of genes coding resistance (bla_OxA-61, tet(O), tet(A) cmeA, cmeB, cmeC, and gyrA (Thr-86-Ile mutation)), with the efflux pump CmeABC being the most prevalent. All antimicrobial resistance-encoded genes co-circulated, except for bla_OXA-61, which moved independently. The minimum inhibitory concentration (MIC) values of two out of three antibiotics (representing different classes) were reduced when the strains tested were exposed to carbonyl cyanide 3-chlorophenylhydrazone (CCCP), a known efflux pump inhibitor. The same result was obtained with the addition of CCCP to the MIC values of bile salts. These results lead to the conclusion that Campylobacter species are present in an impressive diversity in backyard chicken tissues and that they exert a significant resistance to antibiotics, raising a potential danger for public health.

Keywords: Campylobacter; antibiotic resistance; blaOxA-61; cmeA; cmeB; cmeC; ecology; free-grazing chicken; gyrA (Thr-86-Ile mutation); tet(A); tet(O).

Grants and funding

This research received no external funding.