Development and application of real-time TaqMan RT-PCR assay for improved detection of classical swine fever virus in slaughtered pigs

Classical swine fever (CSF) is an economically devastating disease of pigs. Instrumental to the control of CSF is a well-characterized sensitive assay that can deliver a rapid and accurate diagnosis before the onset of clinical signs. With this objective, a real-time fluorogenic-probe hydrolysis (TaqMan) reverse transcription-polymerase chain reaction (RT-PCR) assay was developed for rapid and specific detection of classical swine fever virus (CSFV) and applied on samples derived from infected slaughtered pigs. Apair of PCRprimers targeting 5′-non-coding region (CSFL1 and CSFR1) in conjunction with a CSFV-specific fluorogenic probe (CSFP1) was designed and assessed in real-time PCR. During PCR, when the target of interest was present, the CSFV specific FAM-labeled TaqMan probe annealed to the amplicon between the forward and reverse primers and was subsequently cleaved via the 5^∥-3^∥ exonuclease activity of the DNA polymerase resulting in the release of the fluorescent reporter dye. This assay was found to be rapid and strain-specific for CSFV detection.