| dc.description.abstract | The study helps to provide scientific data on Acute Hepatopancreatic Necrosis Disease which appeared and caused serious mortality in shrimp farm in coastal provinces of the Mekong Delta of Vietnam. General clinical signs at the pond sampling included pale to white and significant atrophy of hepatopancreas (HP), soft shells and empty guts. Samples from 15 shrimp ponds were collected for bacteriology and histopathology. Bacterial samples were directly inoculated on TCBS agar and Chrome agar that clearly formed V. parahaemolyticus colonies. The challenge results showed that cumulative shrimp mortality after injection is higher than mortality after immersion and the number of dead shrimp proportional increases as compared with the challenge doses. After 36 hours immersion challenge with the bacterial concentration of 108 CFU mL-1 and after 12 hours injection challenge with the injection dose of 106 CFU shrimp-1, cumulative shrimp mortality reached 100%. Histopathological structure of infected shrimp expressing typical signs on tissue recovered from the HP of shrimp samples was changed during infected periods. Histopathological changes were found that sloughing of cells, the formation of granuloma, the combination of granuloma formation and cells sloughing.
Keywords:
Vibrio parahaemolyticus, Early Mortality Syndrome, Acute hepatopancreatic necrosis disease/syndrome, infection, immersion histopathology, challenge. | en_US |
