Acute Hepatopancreatic Necrosis Disease (AHPND) is a widespread disease targeting cultured shrimps, which results in heavy losses in many regions around the world including Vietnam. The causative agent of the disease is Vibrio paraheamolyticus which is a Gram-negative bacterium present ubiquitously in marine environment. However, this normal floral organism once acquired a plasmid containing Pir- toxin encoding gene (AHPND plasmid) can transform into a highly toxic strain (AHPND strain) with the ability to kill a large number of cultured shrimps in a short period. | Investigating the production of extracellular enzymes of vibrio parahaemolyticus strains isolated in Vietnam