Prevalence and antimicrobial resistance of Campylobacter species isolated from the avian eggs

• Campylobacter jejuni was more frequently isolated than Campylobacter coli.
• Campylobacter prevalence was significantly higher in summer than in autumn.
• The isolated Campylobacters showed highest sensitivity to gentamicin and spectinomycin.
• Campylobacters were detected in a total of 7% eggshell of chicken samples.
• Campylobacter spp. were also detected in 2.5%, of the eggshell of ostrich.

Campylobacter is one of the most important food borne pathogens that cause bacterial gastroenteritis worldwide. The most commonly isolated species in humans are Campylobacter jejuni (C. jejuni) and Campylobacter coli. The emergence of antimicrobial resistance in Campylobacter spp. has been a growing public health concern globally. Information about antimicrobial resistance of Campylobacter at different levels of production is important for the development of control strategies for this pathogen. This study was conducted to determine the prevalence and antimicrobial resistance of Campylobacter spp. isolated from different eggs from different avian species in Iran. A total of 440 egg samples were collected from different avian and analyzed for the presence of Campylobacter spp. in eggshell and eggs content under sterile conditions using Campylobacter selective agar base and the species were identified by biochemical tests. The suspected colonies were subjected to PCR assay for final confirmation as Campylobacter spp., and identification of C. jejuni or Campylobacter coli. Antimicrobial susceptibility testing was performed by the Kirby–Bauer disk diffusion method using Mueller Hinton agar. Campylobacters were detected in a total of 7 out of 100 (7%) eggshell of chicken samples and in 3 out of 60 (5%) eggshell of duck samples. In addition, Campylobacter spp. were also detected in 3.3%, 2.5%, 4.2%, 5% and 3.8 of the eggshell of goose, ostrich, partridge, quail and turkey samples, respectively. The overall prevalence rate of Campylobacter species from different avian eggs was found to be 7.7% (34/440). Among different avian egg samples, Campylobacter jejuni was more frequently isolated 28 (n = 28, 6.3%) than C. coli 6 (n = 6, 1.3%). In addition, the prevalence of C. jejuni was highest in summer and lowest in autumn. In this study Campylobacter spp. showed significant difference in resistance pattern with tetracycline and ciprofloxacin but gentamicin resistance was not found in both C. coli and C. jejuni isolates. Therefore, gentamicin is safe and effective drugs for the treatment of human campylobacteriosis if avian egg is considered as the source of infection.