Infection rate and SSU rRNA gene analysis of microsporidium caused disease in brackishwater shrimp

Abstract

A total of 238 shrimps (52 post-larvae and 186 commodity shrimps) were collected from the shrimp farms, suspecting infection with microsporidium in Ninh Thuan, Kien Giang and Bac Lieu provinces as materials for this study. Total DNA from these samples were extracted to identify the EHP infection rate by PCR method using specific primers EHP-510F/ EHP-510R. The PCR result showed that the EHP infection rate of shrimps in Ninh Thuan, Kien Giang and Bac Lieu  provinces was  19.44%; 1.16%; 2.27%, respectively; of which, the infection rate of the commodity  shrimps was  higher  than that of the post-larvae. The result of analyzing 23 SSU rRNA sequences from 23 shrimp samples indicated that the isolated microsporidium strains in Viet Nam belonged to Enterocytozoon hepatopenaei species, and  this species related closely  with Nucleospora salmonis, Agmasoma penae, which caused diseases in fish.