The effects of physiological and biochemical index for Penaeus vannmei infected with Vibrio parahaemolyticus

Abstract:

The effects of physiological and biochemical index for white-leg shrimps(Penaeus vannmei)infected with Vibrio parahaemolyticus were studied in this paper.It is a kind of bacteria-Vibrio parahaemolyticus that was isolated from hepatopancreas of diseased shrimps farmed under natural conditions.The infection experiment that healthy shrimp muscles were injected with the isolated bacteria-Vibrio parahaemolyticus was carried out.After injection shrimp mortality was positive interrelationship to duration time and the injection concentration of Vibrio parahaemolyticus,and was negative interrelationship to semilethal concentration(LD50).The tests showed that the activity of SOD and LSZ in muscle and hepatopancreas of shrimp declined,but activity of POD was ascendant with increase of injection concentration of Vibrio parahaemolyticus.The EST bands showed absence.Tissue specific of MDH was very distinct,the expressions of EST and MDH in muscle were most strong among examined tissues.After injection of bacterial-Vibrio parahaemolyticus immunity system of shrimp was destroyed that resulted in immunity function damaged,the abilities of preventing disease and disease resistance declined,shrimps suffered from illness,even died.