Bacterial diseases of penaeid shrimps : an Asian view

In the past 5 Yr, bacterial diseases have become limiting factors in penaeid culture systems, their effects becoming directly proportional to the growth of the industry in terms of severity and imoact. Although eight bacterial genera have been associated with these problems, only two groups accur quit commonly: filamentous bacteria and vibrios, with the latter beibg more impact. Many Vibrio species have been reported in penaeids: Vibrio alginolyticus, V.cholerae (non-01), V. damsela, V. fluvilis, V.nereis, V. splendidus, V. tubiashii, V. vulnificus, V. parahaemolyticus, and V. harveyi. Interestingly, the last three species, all non-sucrosefermenters, are the most dominat. Diagnosis has beed done mostly through conventional bacteriology and histopathology, although development and use of more rapid detection methods like indirect fluorescent antibody technique, monoclonal antibodies, and other enzyme immunoassays are in demand to improve monitoring and survellance. Because of the conflict between the use of chemotherapeutants and the evironmental hazards that go with it, many researches are now poised on non-medicinal approches to solve bacterial diseases problems.