Histopathology and Molecular Characterization of Microsporidian Parasites in Cultured Shrimp Penaeus Monodon Fabricius 1798 of Bangladesh

Abstract

Black tiger shrimp (Penaeus monodon Fabricius 1798) cultured in Bangladesh was investigated for the presence of microsporidian parasite. Histological section of hepatopancreas showed a large number of microsporidian spores under light microscopy. Spores under scanning electron microscope appeared oval shapes. Histology of infected shrimps showed severe degeneration of hepatopancreatic tubules. Early and late stage of microsporidian parasites in hepatopancreatic tubules were also observed. DNA extracted from the hepatopancreas of shrimps were subjected to PCR amplification using primers targeting microsporidian SSU rRNA gene. The PCR amplified an expected product of ~328 bp and the sequences showed 81 -82% identity with the Paranucleospora theridion reported from western Norway in 2008. Further screening of field samples was carried out using EHP-specific primers. DNA extracted from ten hepatopancreas samples of P. monodon were tested and none found to be positive for EHP (Enterocytozoon hepatopenaei). This is the first report for the identification of microsporidian parasites in cultured shrimp along the south-west region of Bangladesh.