Development of a Conventional RT-PCR Assay for Rapid Detection of Porcine Deltacoronavirus with the Same Detection Limit as a SYBR Green-Based Real-Time RT-PCR Assay

Porcine deltacoronavirus (PDCoV) is a newly discovered coronavirus, which belongs to the family Coronaviridae. It causes watery diarrhea, vomiting, and dehydration in newborn piglets. A sensitive RT-PCR method is urgently required to detect PDCoV infection. In this study, we developed and evaluated a conventional RT-PCR assay and a SYBR green-based real-time RT-PCR assay that targeted the PDCoV n gene. Both assays are specific and have the same limit of detection at 2 × 10(1) copies of RNA molecules per reaction. Eighty-four clinical samples were subjected to both conventional RT-PCR and real-time RT-PCR, and the same positive rate (41.7%) was achieved, which was much higher than the positive rate (26.2%) using a previously described one-step RT-PCR technique. In summary, a conventional RT-PCR technique was successfully established for the detection of PDCoV with the same detection limit as a SYBR green-based real-time RT-PCR assay.