Development of multiplex oligonucleotide microarray for simultaneous detection of six swine pathogens

In order to establish a high-throughput identification technique that simultaneously detects six major pathogens including APP, HPS, PRRSV, Mhp, PCV-2 and CSFV, six pairs of primers and probes were designed based on the specific conservative sequences of the pathogens, a multiplex PCR system was developed, hybrid parameters were optimized, and evaluation of the technology was performed. The results showed that the present detection method had a sensitivity of 5.8 × 102copies/μL for APP, 7.8 × 103 copies/μL for HPS, 6.8 × 103 copies/μL for Mhp, 6.3 × 102 copies/μL for PCV-2, 4.8 × 103 copies/μL for PRRSV, and 5.5 × 102 copies/μL for CSFV, respectively; and it produced no cross reaction against the other nine pathogens like swine-origin pseudorabies virus, porcine parvovirus, Japanese B encephalitis virus, swine vesicular disease virus, vesicular stomatitis virus, foot-and-mouth disease virus, bluetongue virus, peste des petits ruminants virus and salmonella. Application of the multiplex oligonucleotide microarray established here to testing 285 clinical blood samples indicated a single infection rate of 18.2 % (52/285) and a mixed infection rate of 6.3 % (18/285) which were consistent with the results of the sequencing verification. This technique might serve as a rapid and high-throughput method of detection for epidemic investigation and clinical diagnosis of multiple pathogens.