A multiplex PCR for simultaneous detection of porcine circovirus type 2, porcine parvovirus, porcine reproductive and respiratory syndrome virus, and classical swine fever virus in pig.

A multiplex polymerase chain reaction(PCR)-based method was designed for simultaneous detection of four main viruses involved in respiratory and/or reproductive failure in piglets(porcine circovirus type 2 ,porcine parvovirus ,porcine reproductive and respiratory syndrome virus ,and classical swine fever virus ).Each of the four pairs of oligonucleotide primers exclusively amplified the targeted fragment of the specific viruses.The sensitivity of the multiplex PCR using purified plasmid constructs containing the specific viral target fragments was 48 pg for PRRSV and CSFV,0.48 pg for PPV and PCV-2.A total of 76 specimens from piglets with symptoms of respiratory and/or reproductive failure were collected in China during June 2006 to July 2007.All specimens were detected at least one of 4 viruses by multiplex PCR.Coinfections with these viruses were identified in 26 specimens(34.2%).Therefore,this method may be a rapid,sensitive,and effective etiological diagnostic tool for the routine surveillance of viral infections in pigs.