Genetic Heterogeneity and Antibiotic Susceptibility of Vibrio alginolyticus Strains Isolated from Horse-Mackerel (Trachurus trachurus L., 1758)

Abstract: This study was performed to investigate the presence of halophylic Vibrio spp. in horse-mackerel (Trachurus trachurus L., 1758). In total, 80 fish samples were collected from fish markets and supermarkets between 04.04.2006 and 16.05.2006 in the city of Mersin. All fish samples were microbiologically tested for halophylic Vibrio spp. Nine (11.25%) Vibrio spp. strains were isolated and identified as V. alginolyticus. Molecular epidemiological discrimination and antimicrobial susceptibility patterns of V. alginolyticus strains were also analysed by arbitrarily primed polymerase chain reaction (AP-PCR) and Kirby-Bauer disc diffusion, respectively. Genotypic heterogeneity of these 9 isolates discriminated by AP-PCR determined that while only 3 isolates were from the same genotypic source the other 6 isolates were from different sources. All isolates were resistant to ampicillin, cephalothin, and streptomycin, and susceptible to levofloxacin, ofloxacin, cefotaxime, nalidixic acid, tetracycline, piperacillin-tazobactam, chloramphenicol, imipenem, and aztreonam. One isolate was resistant to cefepime, 1 to nitrofurantoin, and 1 to ciprofloxacin. One of the 9 isolates was susceptible to erythromycin and 1 to novobiocin, and 3 isolates were susceptible to sulbactam-cefoperazone.