RAPID, SPECIFIC, AND SENSITIVE ON-SITE DIAGNOSIS OF MICROSPORIDIAN Enterocytozoon hepatopenaei ON POCKITTM SYSTEM, A FIELD-DEPLOYABLE TOOL
Pathogen detection by polymerase chain reaction (PCR) assays is a powerful tool to help maintain bio-security and improve overall shrimp production at large-scale facilities. The POCKITTM Nucleic Acid Analyzer (GeneReach), a cost-effective field-deployable tool based on fluorescent probe insulated isothermal PCR (iiPCR), could provide the same benefit at various aquaculture facilities. This system automatically generates simple readouts from nucleic acid samples within one hour using lyophilized reagents, which allows shipping and storage without refrigeration. IQ Plus assays are available for important shrimp diseases, such as Enterocytozoon hepatopenaei (EHP), acute hepatopancreatic necrosis disease/early mortality syndrome and white spot syndrome virus.
Here we show the results of an IQ Plus kit for Enterocytozoon hepatopenaei. Causing white feces disease associated with slow growth of Penaeus monodon and Litopenaeus vannamei, EHP has become a major concern for the shrimp farming industry. Targeting the small subunit rRNA (SSU) gene of EHP, the IQ Plus Kit could be used to monitor any potential threats of white feces disease by screening for the presence of EHP in water and shrimp.
The detection limit of the established assay was of about 9 copies of standard DNA (Table 1). The IQ Plus Kit generated no signals from host genomic DNA and Nosema ceranae (Microsporidia), indicating excellent specificity in detecting EHP. Performance of IQ Plus Kit is detecting SSU of EHP in feces and PL was comparable to that of a published nested PCR detection method. Taken together, the established assay is useful tools for timely biosecurity and managing the white feces disease.