The abnormal characters and types of bacterial detected in mud crab (Scylla sp.) with red thoracic-abdominal syndrome

Abstract

Abnormal characteristics and types of bacterial detected in mud crabs collecting from Samut Songkhram and Chanthaburi Provinces during October 2008 to February 2009 were observed. It was found that the infected crabs had brown to red abdominal thorax, chela, joints and claws and the fibrous muscle were clearly white. Haemolymph of those crabs were classified the severity of the syndrome into five groups; transparent (group I), transparency orange (group II), translucent brown (group III), cloudy orange (group IV) and opaque white (group V). Crabs in group IV and V got unclotted substances which were dispersed in organelles resulted to die very fast. The bacterial identification of infected mud crab present 3 species: Vibrio alginolyticus, Vibrio parahaemolyticus and Shewanella putrefaciens.