Özet:

The aim of this study is to identify of the isolated bacteria strains from disease outbreaks in cultured sea bass (Dicentrarchus labrax L., 1758) in floating net cages in the Eastern Black Sea Region of Turkey. The profiles of antibiotics against disease agents were determined. The kidney and spleen of diseased sea bass that showed typical disease symptoms was streaked on the surface of tryptic soy agar (TSA) added with 1.5 % sodium chloride, and was incubated in the cooled incubator at 20±1°C for 48 hours. To identify of isolated bacteria was carried out by using conventional biochemical tests, the API 20E system tests and the PCR method. All isolates were inoculated in API 20E system test kits by adjusting to a turbidity matching a 0.5 McFarland standard in sterile 1.5% saline water. PCR assay was subjected to using a universal 16s rRNA gene primers to detect V. parahaemolyticus. All isolates showed β hemolysis on blood agar (with 5% sheep blood), and good growth in peptone water containing 7% NaCl. According to the 20E system and conventional biochemical test results were determined that all isolates were V. parahaemolyticus. All strains were confirmed as 98% V. parahaemolyticus by using PCR assay with 16S rRNA. Results of the testing susceptibility to antibiotics showed that V. parahaemolyticus isolates were resistant to 100% sulphamethoxazole, 84.4% ampicillin, 71.9% erythromycin, 62.5% oxytetracycline 56.3% trimethoprim-sulfamethoxazole and 46.9% streptomycin, but all strains were found susceptible to oxolinic acid, enrofloxacin and florphenicol.

Anahtar Kelimeler: