Chapter 19 - Acute hepatopancreatic necrosis disease

Abstract

Acute hepatopancreatic necrosis disease (AHPND) is caused by virulent strains of Vibrio bacteria containing a pVA1 plasmid with genes that encode toxins PirAvp and PirBvp. Outbreaks of AHPND have caused dramatic reductions in shrimp production in South-East Asia and Latin America. This disease usually causes massive mortality within 30–35 days after stocking postlarvae in shrimp ponds. The two major farmed species, Pacific white shrimp Penaeus vannamei and black tiger prawn P. monodon, have been demonstrated to be susceptible to AHPND. The main clinical signs include a pale to white, atrophied hepatopancreas and an empty stomach and gastrointestinal tract. A prominent, characteristic, histopathological feature is the sloughing of hepatopancreas tubule epithelial cells into the lumens. Strict sanitary and biosecurity practices, along with the use of high-quality postlarvae and the attentive, careful management of broodstock and production facilities can reduce both the risks and impacts of AHPND in commercial shrimp farms.