Prevalence of Enterocytozoon hepatopenaei (EHP) in Vinh Long Province, Vietnam and Potential of Bamboo Charcoal in EHP Control in White Leg Shrimp (Litopenaeus vannamei) Culture

Enterocytozoon hepatopenaei (EHP) has been caused the substantial lost of production in shrimp farms in Vietnam. This study investigated the prevalence of EHP in white leg shrimp (Litopenaeus vannamei) culture in Vinh Long province, Vietnam and examined the effect of bamboo charcoal on survival, growth and EHP control in white leg shrimp.

A total of 58 shrimp samples collected randomly from 58 shrimp ponds at 53 shrimp farms in Vinh Long province was examined for the prevalence of EHP. Beside that, feed supplemented bamboo charcoal (FSBC) at 0%, 1% and 2% was examined for their effects on survival and growth of white leg shrimp and EHP control in white leg shrimp culture.

This study found that EHP can be detected in 28/58 (48.28%) in white leg shrimp samples collected from shrimp ponds. Common clinical symptoms of EHP infected shrimp showed slow growth, size variation, segmented intestinal food and pale hepatopancreas (HP). Several EHP positive samples were found with white feces syndrome. After 3 weeks of culture, FSBC showed no effect on survival and growth of white leg shrimp. After 2 weeks fed EHP infected tissue, shrimp fed bamboo charcoal showed significantly higher survival rates compared to animals fed feed without bamboo charcoal and the cycle threshold value by real time PCR in shrimp fed FSBC at 2% was significantly higher than that in shrimp fed feed without bamboo charcoal. In conclusion, EHP was prevalent relatively high in white leg shrimp ponds in Vinh Long province, Vietnam and bamboo charcoal could be a potential source in EHP control in white leg shrimp culture.