Bacteria Recovered from Cultured Gilt-Head Seabream (Sparus aurata) and their Antimicrobial Susceptibilities

Abstract

DOI : 10.26650/EuroJBiol.2018.346175  Objective : Gilt-head seabream (Sparus aurata) is an important species for Turkish aquaculture and bacterial diseases are one of the limiting factors for the production of this species. The aim of this study is the identification of the bacterial disease agents in cultured gilt-head seabream in Turkey and the determination of their antibacterial susceptibilities. Materials and Methods : In this study, 27 diseased gilt-head seabream samples between 3-130 g, showing various clinical symptoms, were examined bacteriologically. Bacterial isolates recovered from moribund fish samples were identified by using standard bacteriological methods and API 20E rapid identification strips. Antibiotic susceptibility tests of 10 different substances against these isolates were determined by using Kirby-Bauer disc diffusion method. Results : Vibrio anguillarum, V. scophthalmi, V. logei, V. harveyi, Pseudomonas anguilliseptica, P. stutzeri, Staphylococcus sp. and Micrococcus luteus isolates were isolated from diseased fish samples as pure and mixed infection. It was detected that API 20E may give erroneous results for fish pathogenic bacteria since they are not included in the database of the kit. Generally, enrofloxacin, florphenicol and oxytetracycline were found to be the most effective antibiotics against bacterial isolates. Conclusion : This study is the first report for V. scophthalmi, V. logei, V. harveyi, P. stutzeri and M. luteus infections of gilt-head seabream in Turkey.