2016-2018年吉林省猪圆环病毒2型流行病学调查及序列分析

Epidemiological Survey and Analysis of Porcine Circovirus Type 2 in Jilin Province from 2016 to 2018

为了调查吉林省猪圆环病毒2型(PCV2)的流行情况,对2016-2018年采集的434份疑似PCV2感染病料或血清样品进行PCR检测,并对其中分离的2株PCV2(2017/2018)进行全基因组的扩增、测序及遗传进化分析。PCR检测结果显示,PCV2的阳性率为38.5%。基因测序结果显示,PCV2-2017和PCV2-2018全基因组长度为1767 bp。全基因同源性分析显示,PCV2-2017与法国株AF055394同源性最高,可达99.8%,与PCV2-2018同源性最低,为80.1%;PCV2-2018与法国株AY322001同源性最高达99.8%,与上海株GU124593同源性最低,为77.2%。遗传进化分析结果显示,与国内外参考毒株比较,PCV2-2017和PCV2-2018处于2个不同的分支中,其中1个分支中PCV2-2018与国内GU370064、AY691169、AY969004、DQ180393及国外AY322001、AB426905毒株亲缘关系较近;PCV2-2017与HM102350、JQ809464、GU124593、AF055394、AF055391、GU325757、JX512856组成第2个分支,与法国株AF055394亲缘关系最近,同属于PCV-2b亚型,与JQ809464、HM102350、GU124593亲缘关系也较近。本试验将为后续PCV2的诊断防控及病毒学研究提供参考依据。

To investigate the prevalence of porcine circovirus type 2(PCV2)in Jilin province,a total of 434 pathological or serum samples of pigs with PCV2 collected during 2016 to 2018 were detected by PCR.The genome of PCV2(2017/2018)was amplified,sequenced and analyzed.The positive rate of PCV2 in pigs was 38.5%.The whole genome of PCV2(2017/2018)was 1767bp in length.Whole gene homology analysis showed that PCV2-2017 had the highest homology with the French strain AF055394,up to 99.8%,and the lowest homology with PCV2-2018,up to 80.1%.PCV2-2018 had the highest homology of 99.8%with the French strain AY322001,and the lowest homology with the Shanghai strain GU124593,which was 77.2%.The results of genetic evolution analysis showed that,compared with the domestic and abroad reference strains,PCV2-2017 and PCV2-2018 were in two different branches.In one branch,PCV2-2018 was closely related to the domestic strains GU370064,AY691169,AY969004,DQ180393 and foreign strains AY322001 and AB426905.PCV2-2017 formed a second branch with HM102350,JQ809464,GU124593,AF055394,AF055391,GU325757 and JX512856.It was most closely related to the French strain AF055394 and belongsed to the PCV2-2b subtype.It was also closely related to JQ809464,HM102350 and GU124593.This study will provide some data for diagnosis,prevention and control of PCV2 and the subsequent scientific research.