2013~2017年江西省猪圆环病毒2型分子流行病学调查

为掌握江西地区猪圆环病毒2型（PCV2）的分子流行病学及其遗传变异情况，本研究运用实验室已建立的PCR方法对2013~2017年采集自江西省南昌市、宜春市、新余市、赣州市、吉安市、九江市、上饶市、抚州市、景德镇市、鹰潭市等10个地区的1 082份疑似PCV2感染猪病料组织进行病原学检测，并通过PCR扩增、克隆和基因测序对PCV2的全基因组序列进行分析。研究表明，1 082份病料中有610份为PCV2阳性，总阳性率为56.4%，其中2013~2017年阳性率分别为52.7%、48.8%、58.5%、71.0%和67.4%。共获得89株PCV2全基因组序列，其中有83株为PCV2b基因型，其中53株归类于PCV2b-1C基因亚群，30株归为PCV2b-1A/1B基因亚群；6株为PCV2a型。测序毒株与参考毒株ORF2基因核苷酸、氨基酸序列同源性分别为88.9%~100.0%和86.0%~100.0%；氨基酸序列分析表明，Cap蛋白存在20个氨基酸突变位点。本研究表明，江西地区猪群中PCV2的主导基因型为PCV2b，其中又以PCV2b-1C基因亚群占据主导地位，同时也存在少量PCV2a基因型。

Molecular Epidemiological Investigate of Porcine Circovirus Type 2 in Jiangxi Province During 2013 to 2017

To investigate the molecular epidemiology and genetic diversity of porcine circovirus type 2 (PCV2) in Jiangxi province,1 082 tissue samples were collected during 2013 to 2017 from suspected pigs in 10 regions (including Nanchang,Yichun,Xinyu,Ganjiang,Ji'an,Jiujiang,Shangrao,Fuzhou,Jingdezhen and Yingtan cities) of Jiangxi province were detected for PCV2.And PCV2 isolates complete genome sequences were amplified,cloned and sequenced.The results showed that 610 of 1 082 samples were detected to be positive of PCV2 and the total positive rate was 56.4%.The positive rates from 2013 to 2017 were 52.7%,48.8%,58.5%,71.0% and 67.4%,respectively.The 83 of 89 PCV2 isolates belonged to PCV2b,and 53 and 30 of 83 isolates were grouped into PCV2b-1C and PCV2b-1A/1B,respectively,and 6 isolates belonged to PCV2a.The homology of nucleotides and the deduced amino acid sequence of ORF2 between sequenced strains and reference strains were 88.9% to 100.0% and 86.0% to 100.0%,respectively.Analysis of Cap acid amino sequences showed that there were 20 amino acid mutation sites.This research indicated that the dominant genotype of PCV2 in pigs in Jiangxi was PCV2b,and PCV2b-1C was a dominant subgenotype.At the same time,a small amount of PCV2a subgenotype also existed.