Detection of Enterocytozoon hepatopenaei using an invasive but non-lethal sampling method in shrimp (Penaeus vannamei)

Abstract

The detection of enteric pathogens that cause diseases in shrimp involves the sacrifice of the host to obtain tissue samples for diagnosis. In this study, we describe an invasive but non-lethal sampling methodology using a syringe to collect biopsy samples from the hepatopancreas (HP) of Penaeus vannamei to detect the microsporidian pathogen, Enterocytozoon hepatopenaei (EHP), by qPCR and transmission electron microscopy. EHP was detected in all the infected shrimp by qPCR. The shrimp infected by the microsporidian showed 65% survival at 7 days post-sampling. Transmission electron microscopic examination of the biopsy samples revealed numerous spores of the pathogen. The presence of EHP was further confirmed by histology and in situ hybridization from HP tissue samples. The data shows that a hepatopancreas biopsy could be a viable means of detecting enteric pathogens in shrimp, and the method could be valuable in sampling broodstock and natural populations without the need to sacrifice the animals.

Keywords: Biopsy; Enterocytozoon hepatopenaei; Microsporidia; Non-lethal sampling.