Isolation and characterization of Vibrio owensii from Palk Bay and its infection study against post larvae of Litopenaeus vannamei.

Vibrio is heterotrophic ubiquitous marine bacteria that plays dual role as putative halobiont and potential pathogen. Environment and diseases are inextricable hence the role of vibrio as a potential pathogen in the natural environment must be comprehended. Hence the present study aims at investigating the pathogenicity of Vibrio owensii on the post larvae of Litopenaeus vannamei. V. owensii isolated from the marine natural habitat of the Palk Bay province in India was highly resistant to ampicillin, methicillin, tetracycline and vancomycin. The strain also lacked pathogenicity against the post larvae of L. vannamei due to the absence of major virulence factors viz. Chitinase, phospholipase and hemolytic activity. Presumably this is the first report on the occurrence of V. owensii in the Indian waters therefore there arises a need to carry out more serious research on the pathogenicity of this species on other commercial crustaceans reared in the Indian aquaculture settings in order to apprehend its role as potential pathogen or the contrary.