猪圆环病毒2型、猪繁殖与呼吸综合征病毒及猪细小病毒混合感染的流行病学调查

根据GenBank上发表的PRRSVORF7、PPVVP2及PCV的基因组序列设计合成引物，建立了分别用于检测PRRSV、PPV和PCV的RT-PCR、PCR及复合PCR方法。应用建立的复合PCR方法对送检的127份病料进行了PCV的检测，对鉴定为PCV2阳性的67份病料再分别进行PRRSV和PPV的检测，以确定猪群中PCV2与PRRSV和，或PPV混合感染情况，结果表明，35份样品表现为PRRSV与PCV2混合感染，占样品总数的52．3％；18份样品表现为PCV2与PPV混合感染，占26．9％。另外，还有一定比例的三重感染，共5个样品，占7．5％。由此可见，猪群中PCV2与PRRSV及PPV混合感染比较普遍。

Investigation on Epidemiology of Co-infection of Porcine Circovirus Type 2,Porcine Reproductive and Respiratory Disease Syndrome Virus and Porcine Parvovirus

According to the published genomic sequences of Porcine reproductive and respiratory disease syndrome virus (PRRSV),Porcine parvovirus (PPV) and Porcine circovirus type 2, primers were designed and RT-PCR, PCR and multiplex PCR were set up for the detection of PRRSV, PPV and PCV, respectively. 127 samples were detected for PCV by the multiplex PCR. With the established methods, 67 clinical samples positive for porcine circovirus type 2 (PCV2) were tested for the presence of PRRSV and PPV. The results demonstrated that the co-infection rate of PRRSV/PCV2, PPV/PCV2 and PRRSV/PPV/PCV2 were detected in 52.3% (35/67), 26.9% (18/67) and 7.5% (5/67), respectively. The data obtained in the present study indicated that it is very prevalent for the co-infection of PRRSV, PPV and PCV2.