The survey of porcine teschoviruses in field samples in China with a universal rapid probe real-time RT-PCR assay.

A real-time reverse transcription polymerase chain reaction (RT-PCR) based on TaqMan was established and evaluated for quantitative detection of porcine teschoviruses (PTVs). A pair of primers and a TaqMan probe targeting on the highly conserved sequence of the 5'-untranslated region (5'-UTR) of one to 11 serotypes of PTV were designed. Standard plasmid DNA containing PCR amplification of the 5'-UTR were constructed and used to develop the real-time RT-PCR. The results indicated that the real-time RT-PCR was specific for detection of PTV with a detection limit of 10 copies/μL, but not for porcine parvovirus, porcine circovirus type 2, porcine reproductive and respiratory syndrome virus, pseudorabies virus, classical swine fever virus. The coefficient of variation of inter-assay and intra-assay were less than 3 %. A total of 91 clinical samples were tested by the real-time RT-PCR and virus isolation (OIE 2008) and positive rates were 79.12 % (72/91) and 57.14 % (48/91), respectively. In conclusion, the developed real-time RT-PCR assay was an effective method for detection and quantification of PTV in fields or organs of infected pigs.