Abstract: In order to investigate the prevalence of porcine reproductive failure caused by viruses, 1068 patient samples from 14 pig farms in the vicinity of Taiyuan were detected using multiplex PCR diagnostic methods. The average infection, rate of porcine reproductive and respiratory syndrome virus (PRRSV), classical swine fever virus (CSFV), porcine parvovirus (PPV), pseudorabies virus(PRV) and porcine circovirus type 2 (PCV-2) were 32%,40%,20%,12%,27%, respectively.More than two viruses mixed infection was 39%,two virus infection was 24%. 1572 blood samples were detected using RT-PCR kits for PRRSV RNA and CSFV RNA in 11 cities of Shanxi province from 66 pig farms and 121 free-range pig farm households. The results showed that PRRSV infection rate was 33%. CSFV infection rate was 46%.1593 blood samples were detected to indentify immune antibody titer of CSFV, the average qualified rate was 43.9%. It provides experimental data for working out comprehensive measures to prevent and control the epidemic diseases.

Key words: multiplex PCR; PRRSV; PPV; PRV; PCV-2; CSFV; reproductive failure