RT-PCR-based dot blot hybridization for the detection and differentiation between porcine epidemic diarrhea virus and transmissible gastroenteritis virus in fecal samples using a non-radioactive digoxigenin cDNA probe.

Multiplex reverse transcription-polymerase chain reaction (RT-PCR)-based dot blot hybridization was developed to increase the sensitivity for the detection and differentiation between porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV) in fecal samples. Fecal samples found positive by RT-PCR-based agarose gel electrophoresis were always found positive by RT-PCR-based dot blot hybridization. In addition, 5 out of 10 fecal samples which were negative for PEDV by RT-PCR-based agarose gel electrophoresis were positive for PEDV by RT-PCR-based dot blot hybridization. This RT-PCR-based dot blot hybridization increased 1000-fold in sensitivity for PEDV and 100-fold for TGEV; weakly positive bands in the agarose gel electrophoresis gave a clear positive result with dot blot hybridization.