Shell Disease in Freshwater River Prawn Macrobrachium malcolmsonii (H. Milne Edwards) Due to Induced Infection of Bacterium Aeromonas hydrophilla

The present study was conducted for 50 days in the laboratory to assess the typical signs and symptoms of a particular pathogen Aeromonas hydrophilla in a river prawn Macrobrachium malcolmsonii. In this study, bacterium Aeromonas hydrophilla was inoculated to the water medium of the prawn juveniles through immersion method. The juveniles of M. malcolmsonii exhibited the signs and symptoms of shell disease, such as, erratic movement, lethargic in swimming, of feeding, no molting, black spots on the sclerites and necrosed uropods. The bacterium Aeromonas hydrophilla was reisolated from infected juveniles and tested biochemically to confirm one of the causative agent of shell disease.