Pathological features of hepatopancreas necrosis syndrome in farmed white-leg shrimp (Litopenaeus vannamei) in Ninh Thuan province

Abstract

The farmed white leg shrimp in Ninh Thuan province was died with the un-normal clinic signs such as: empty gut, anorexia, pale, white feces. The shrimp mortality rate could be up to 100%, this caused the heavy loss for the shrimp farmers. Histological study was conducted on 40 diseased and 10 healthy shrimps in order to identify the pathological signs. The studied result showed that severe necrosis inside hepatopancreas was noted in all of the diseased shrimps with the clearly biological signs basing on the diseased stage and level. The abnormalities of hepatopancreas such as: disappearance of the hepatic cells: type B, F and R, sloughing of the epithelial cells, gathering of the blood cells surrounding the lesions and inflammation areas were observed. The abnormalities were not found in other organs of the diseased shrimps. The serious lesions in hepatopancreas could be the cause of mortality. Inclusion body was not found in the epithelial cells of hepatopancreas of the diseased shrimps.