近年湖南省猪圆环病毒2型感染状况的调查及遗传演化分析  

Investigation of Porcine Circovirus 2 Infection Status and Analysis of Genetic Evolution in Hunan Province in Recent Years

作　　者：范杰 邰易润 朱艳丽 陈志雄 胡巧云 陈智 刘甜甜 李欣 范仲鑫[2] 葛猛[1] FAN Jie;TAI Yirun;ZHU Yanli;CHEN Zhixiong;HU Qiaoyun;CHEN Zhi;LIU Tiantian;LI Xin;FAN Zhongxin;GE Meng(College of Veterinary Medicine,Hunan Agricultural University,Changsha 410128,China;Hunan Province Animal Disease Prevention and Control Center,Changsha 410014,China;Changsha Animal and Plant Disease Control Center,Changsha 410000,China)

机构地区：[1]湖南农业大学动物医学院,长沙410128 [2]湖南省动物疫病预防控制中心,长沙410014 [3]长沙市动植物疫病预防控制中心,长沙410000

出　　处：《畜牧兽医学报》2025年第3期1376-1385,共10页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：国家自然科学基金面上项目(32072871);湖南省重点研发计划项目(2023NK2017);云南省重大科技专项计划(202202AE090032)。

摘　　要：本研究旨在掌握近期湖南省各地区猪圆环病毒2型(PCV2)最新的感染和遗传演化情况。本研究运用qPCR方法对2021-2023年采集自湖南省长沙市、岳阳市、怀化市、常德市、株洲市等14个地级市的1244份肥猪的淋巴结、拭子、脑组织及血样通过qPCR进行了病毒核酸检测,筛选出PCV2阳性样品,再通过PCR扩增及测序对PCV2的ORF2基因序列进行分析。结果显示,1244份样品中有778份为PCV2阳性,总阳性率达62.54%,其中邵阳市的PCV2阳性率最高,达92.55%(87/94),郴州市最低,为18.28%(17/93);57株PCV2 ORF2基因测序结果表明,PCV2a、PCV2b和PCV2d占比分别为12.28%、7.02%和80.70%;测序毒株间的ORF2基因核苷酸、氨基酸序列相似性分别为88.5%~100.0%和86.3%~100.0%,存在45个氨基酸差异位点,PCV2d间存在15个差异氨基酸位点,选择压力分析表明,PCV2存在3个阳性选择位点。研究表明:目前,PCV2的突变速率较快,各毒株之间存在较多的氨基酸位点差异,与既往报道相同,本研究中PCV2d已成为绝对优势的流行毒株,PCV2的这些变异可能使现有疫苗保护效果减弱,应予以重视。This study aims to understand the latest infection and genetic evolution of porcine circovirus type 2(PCV2)in various regions of Hunan Province.Using qPCR methods established in the laboratory,this study conducted viral nucleic acid detection on 1244 samples of lymph nodes,swabs,brain tissue,and blood collected from 14 prefecture-level cities in Hunan Province,including Changsha,Yueyang,Huaihua,Changde,and Zhuzhou,from 2021 to 2023.PCV2-positive samples were then screened out,and the ORF2 gene sequences of PCV2 were analyzed through PCR amplification and sequencing.The results showed that 778 of the 1244 samples were PCV2-positive,with an overall positive rate of 62.54%.Among them,Shaoyang City had the highest PCV2 positive rate of 92.55%(87/94),while Chenzhou City had the lowest positive rate of 18.28%(17/93).Sequencing analysis of the ORF2 gene of 57 PCV2 strains revealed that the proportions of PCV2a,PCV2b,and PCV2d were 12.28%,7.02%,and 80.70%,respectively.The nucleotide and amino acid sequence homologies of the ORF2 gene among the sequenced strains ranged from 88.5%to 100.0%and 86.3%to 100.0%,respectively.There were 45 amino acid variant sites among 57 PCV2 strains,and 15 variant amino acid sites among PCV2d strains.Selection pressure analysis indicated that there were three positive selection sites in PCV2.This study suggests that PCV2 is currently mutating rapidly,with significant amino acid site differences among various strains.Consistent with previous reports,PCV2d has become the absolutely dominant epidemic strain in this study.These variations of PCV2 may weaken the protective effect of vaccines,which deserves attention.

关 键 词：猪圆环病毒2型 分子流行病学调查 遗传变异 ORF2基因 选择压力 

分 类 号：S852.659.2[农业科学—基础兽医学]