2021年浙江省部分地区猪圆环病毒2型及3型的遗传变异分析  

Analysis of genetic variation of porcine circovirus type 2 and porcine circovirus type 3 in Zhejiang Province in 2021

作　　者：于浩然 甘诗琪 刘雅琦 董婉玉 杜静 周兴东 周莹珊 王晓杜 YU Hao-ran;GAN Shi-qi;LIU Ya-qi;DONG Wan-yu;DU Jing;ZHOU Xing-dong;ZHOU Ying-shan;WANG Xiao-du(College of Animal Science and Technology&College of Veterinary Medicine,Zhejiang A&F University,Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province,Zhejiang Provincial Engineering Research Center for Animal Health Diagnostics&Advanced Technology,Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management,China-Australia Joint Laboratory for Animal Health Big Data Analytics,Hangzhou 311300,China)

机构地区：[1]浙江农林大学动物科技学院/动物医学院/浙江省畜禽绿色生态健康养殖应用技术研究重点实验室/动物健康互联网检测技术浙江省工程实验室/浙江省动物医学与健康管理国际科技合作基地/中澳动物健康大数据分析联合实验室,浙江杭州311300

出　　处：《中国预防兽医学报》2023年第6期643-648,共6页Chinese Journal of Preventive Veterinary Medicine

基　　金：浙江省农业重大技术协同推广项目(2021XTTGXM02-05);杭州市农业与社会发展科研项目(20201203B61);金华市农业重点研发项目(2022-2-022)。

摘　　要：为了解2021年中国浙江省各地区猪圆环病毒2型(PCV2)和猪圆环病毒3型(PCV3)的遗传变异情况,本研究采用PCR技术对不同地区来源的702份病料样品检测。选取10个PCV2阳性样品进行全基因序列扩增和同源性及遗传演化分析。同时对已测序的26个PCV2 ORF2基因和24个PCV3 ORF2基因分别进行同源性分析,以及对Cap蛋白氨基酸序列进行比对分析。结果显示,病料样品中PCV2的总阳性率为32.8%(230/702),PCV3的总阳性率为15.0%(105/702)。其中PCV2在血清样品中的检出率最高,而PCV3在粪便样品中的检出率较高。PCV2和PCV3混合感染血清阳性率为6.1%(33/539),且仅在血清样品中有混合感染。测序筛选后共获得6个PCV2全基因序列,其中5个全基因序列为1767 bp,1个为1708 bp。PCV2全基因序列与24个国内外PCV2参考株全基因序列相比,同源性为94.1%~98.9%。通过全基因遗传进化树显示,6个PCV2全基因有5个PCV2d亚型和1个PCV2b亚型。ORF2基因序列的同源性结果显示,PCV2与PCV2疫苗株的同源性为90.2%~95.3%;PCV3与PCV3参考株的同源性为99.2%~99.4%,与PCV2疫苗株的同源性仅为32%,可能影响PCV2疫苗的保护效力。通过ORF2编码的Cap蛋白氨基酸序列比对结果显示,本研究中的PCV2 Cap蛋白氨基酸序列有20处变异,其中R^(59)K、K^(63)R、A^(68)N、R^(89)L、S^(90)T、S^(121)T、T^(134)N、S^(169)R、E^(210)D的变异揭示了该地区PCV2b亚型正逐渐向PCV2d亚型转变。上述结果表明,浙江省部分地区的PCV2d亚型已成为主要的流行基因型,且PCV3与PCV2疫苗株同源性较低。本研究结果丰富了浙江省PCV的分子流行病学资料,为相应疫病的防控提供一定的参考依据。Porcine circovirus(PCV)causes postweaning multisystemic wasting syndrome and immunosuppression in weaned piglets.To understand the genetic variation of porcine circovirus type 2(PCV2)and porcine circovirus type 3(PCV3)in various regions of Zhejiang Province,China in 2021,total 702 samples that collected from different regions were tested using PCR in this study.Ten PCV2-positive samples were selected for whole genome amplification and sequence analysis.26 sequenced PCV2 ORF2 genes and 24 sequenced PCV3 ORF2 genes were analyzed for homology and amino acid alignment of the encoded Cap proteins.The results showed that the positive rates of PCV2 and PCV3 were 32.8%and 15.0%,respectively.PCV2 had the highest detection rate in serum samples,while PCV3 had a higher detection rate in fecal samples.The co-infection rate of PCV2 and PCV3 was 6.1%,and the co-infection was found only in serum samples.After sequencing,a total of six full gene sequences of PCV2 were obtained by sequencing screening,of which five were 1767bp and one was 1708bp.The PCV2 whole gene sequence showed 94.1%-98.9%homology compared with the sequences of 24 domestic and foreign reference strains.A whole-genome genetic evolutionary tree showed that the PCV2 whole genes were PCV2d subtype(5/6)and PCV2b subtype(1/6).PCV2 ORF2 gene sequence showed 90.2%-95.3%homology to PCV2 vaccine strain.The sequence of PCV3 ORF2 gene was 99.2%-99.4%homologous with PCV3 reference strain,while,its homology with the PCV2 vaccine strain was only 32%.This may affect the efficacy of vaccine protection.The comparison of the amino acid sequence alignment of the Cap protein encoded by ORF2 showed that there were 20 mutations in the Cap protein of PCV2.Most importantly,the R^(59)K、K^(63)R、A^(68)N、R^(89)L、S^(90)T、S^(121)T、T^(134)N、S^(169)R、E^(210)Dvariants revealed that the PCV2b subtypes were gradually shifting to the PCV2d subtypes in this region.The results of this study indicate that the PCV2d subtype has become the main prevalent genotype in some areas of Zheji

关 键 词：猪圆环病毒2型 猪圆环病毒3型 ORF2基因 序列分析 

分 类 号：S852.65[农业科学—基础兽医学]