Freshwater prawn (Macrobrachium rosenbergii, de Man, 1879) is an important commercial species due to property as food supply as well as a valuable export product. In the last several years, prawn diseases have had a devasting effect on world prawn farming. Such diseases increase risk, deterring investment and commercial development. Out breaks of disease in prawns is often attributed to bacterial infection . Vibrio species have been reported as the causative agents for numerous disease outbreaks These species cause some diseases such as vibriosis and chitinolytic bacterial shell disease. Vibrios are a ubiquitous and predominant component of prawn culture environment and comprise a major part of the normal flora of crustaceans