猪腺病毒血清3型PCR检测方法的建立及其初步流行病学调查

Establishment of the PCR assay for porcine adenovirus type 3 detection and primary epidemiology survey of the virus in Sichuan province

为建立一种猪腺病毒3型（PADV-3）的检测方法，本研究根据PADV-3E1B基因保守序列设计一对引物，建立了PcR检测方法。特异性试验结果显示，该方法仅对PADV．3扩增出247bp的目的片段。而对猪瘟病毒、猪流行性腹泻病毒、猪博卡病毒、猪传染性胃肠炎、猪伪狂犬病毒、猪圆环病毒、大肠杆菌、猪链球菌均无特异性扩增；敏感性试验结果显示，该方法对PADV-3最低检测量为3．7×10-5拷贝／μL。应用该方法对我国四川省23个规模化猪场进行流行病学调查，结果显示PADV．3阳性率达到14．72％，在腹泻猪群中阳性率为17．34％，并且显著高于非腹泻猪群（6．41％），PADV．3在保育猪群中感染率最高（26．32％），表明PADV．3在我国四川省猪群中广泛流行。本研究建立的PCR检测方法特异性强、灵敏度高，可以应用于猪群中PADV．3的流行性调查。

In order to establish a rapid assay for detecting porcine adenovirus type 3 （PADV-3）, the PCR method was developed with a pair of special primers targeting on the virus E1B gene. Then, a 247 bp DNA fragment was specifically amplified from PADV-3 with a detection limit of 3.7×105 copies/μL by this assay, but no any amplifications detected from classical swine fever virus, porcine epidemic diarrhea virus, porcine bocavirus, transmissible gastroenteritis virus, porcine pseudorabies virus, porcine circovirus, E.coli and S.suis. In addition, a total of 326 fecal samples collected from different farms in Sichuan province were detected by the established method, the positive rate was 14.72%, and the PADV-3 positive rate among diarrhea pig （17.34%） was significantly higher than that of the pigs without diarrhea （6.41%）. Furthermore, the positive rate to nursery piglets was the highest （26.32%）, showing that PADV-3 widely epidemic among pigs in Sichuan province. These results demonstrated that the PCR assay was sensitive and specific to detect PADV-3, which could be applied in the clinic detection and epidemiological survey of the PADV-3 infection in pigs.