The effects of feeding on the development of AHPND causative agent - Vibrio Parahaemolyticus in shrimp farming

Abstract

Acute hepatopancreatic necrosis disease syndrome (AHPND), often known as early mortality syndrome (EMS), has recently caused serious problems to the global shrimp industry. It is known that the causative agent of AHPND is a unique strain of Vibrio parahaemolyticus. There have been observations that AHPND-infected shrimps must not be fed with commercial pellets. Otherwise, mortality would be very high. In other cases, AHPND was observed after a period of sudden increase in feeding demand of the cultured shrimps. However, little scientific evidence is available on the association between the use of commercial shrimp feeds and AHPND causative agent Vibrio parahaemolyticus in culture shrimp pond. This study was carried out to test whether there is a correlation between the availability of shrimp feed pellets and the growth of Vibrio parahaemolyticus. In this study, four treatments were estalbished using fermented cereal and three commercial feeds for feeding shrimp for a period of 17 days. The experimental shrimps were challenged with Vibrio parahaemolyticus at the density of 105 cfu/ml during this period. Results indicated that feeding shrimps with commercial pellets was associated with stronger proliferation of AHPND causing Vibrio parahaemolyticus. Smaller-sized feeds also appeared to induce heavier accumulation of Vibrio parahaemolyticus in bottom water layer. Key words: Vibrio parahaemolyticus, commercial pellets, feeding, AHPND, EMS