Shahmoradi Mehdi, Dehvari Aslam, Motaghi Mohammad Mehdi, Hossein Rameshi and Tadayon Mohammad Hassan1
Pinctada margaritifera (black-lipped pearl oyster) is one of the most important species of mollusks used for the production of breeding pearls. The fatality of Pinctada margaritifera has been observed in all stages of growth, which the reasons were not discussed before. This study aims to isolate, identify, and determine antibiotic susceptibility of vibrionaceae, one of the most pathogenic factors in the Pinctada margaritifera. The process of detecting and identifying bacteria was done based on the culture in TSA and TCBS media, and then biochemical tests. Also, the antibiotic susceptibility of the bacteria was studied using the diffusion disc method. As a result, Four species of Vibrionaceae, including Vibrio harveyi, Vibrio alginoliticus, Vibrio splendidus, and Vibrio angioillarum, have been identified in the gills of Pinctada margaritifera. All of the species were resistant to ampicillin, erythromycin, streptomycin, and oxacillin, sensitive to novobiocin, and semi-sensitive to the oxytetracycline.