分类号:单位代码:10019 密级:学号:S0*******硕士学位论文北京地区犬细小病毒VP2基因序列分析和流行病学调查Sequence analysis of VP2 gene and epidemiological survey ofcanine parvovirus in Beijing研究生:宋永奇指导教师:吕艳丽副教授合作指导教师:申请学位门类级别:农学硕士专业名称:预防兽医学研究方向:兽医微生物学与免疫学所在学院:动物医学院2008年 5 月独 创 性 声 明本人声明所呈交的论文是我个人在导师指导下进行的研究工作及取得的研究成果。
尽我所知,除了文中特别加以标注和致谢的地方外,论文中不包含其他人已经发表或撰写过的研究成果,也不包含为获得中国农业大学或其它教育机构的学位或证书而使用过的材料。
与我一同工作的同志对本研究所做的任何贡献均已在论文中作了明确的说明并表示了谢意。
研究生签名:时间:年月日关于论文使用授权的说明本人完全了解中国农业大学有关保留、使用学位论文的规定,即:学校有权保留送交论文的复印件和磁盘,允许论文被查阅和借阅,可以采用影印、缩印或扫描等复制手段保存、汇编学位论文。
同意中国农业大学可以用不同方式在不同媒体上发表、传播学位论文的全部或部分内容。
(保密的学位论文在解密后应遵守此协议)研究生签名:时间:年月日导师签名:时间:年月摘 要犬细小病毒(Canine parvovirus,CPV)感染是目前危害养犬业的最严重传染病之一。
为了了解CPV的变异情况,本研究在2006-2007年间不同时间采集CPV感染患犬粪便样本20份,经PCR方法从中扩增出了CPV VP2基因,并对该基因进行了序列测定与分析;为了了解本病的流行状况,本研究对临床上常用的CPV检测方法的可靠性进行了评估,并在此基础上对2005-2007年到中国农业大学动物医院诊治的所有有呕吐、腹泻和呕吐或腹泻症状的犬粪便样本的CPV检测结果进行了统计分析,获得如下结果:VP2基因全长1755bp,编码585个氨基酸。
经核苷酸及推导的氨基酸序分析显示,20个样本中,有19个属于CPV-2a,1个为CPV-2b;所有病毒样本VP2的297氨基酸残基位点均发生Ser→Ala的置换;基因型为CPV-2a样本的555氨基酸残基位点均发生IIe→Val的置换。
与经典的CPV-2a/2b参考毒株比较,80.0%(16/20)的样本在324位有Tyr→Ile的置换;样本CPV/BJ005/07和CPV/BJ008/07的139位氨基酸残基由Val置换为Ile;样本CPV/BJ004/07和CPV/BJ050/07分别在226与382位发生置换(Ser→Asn,和Arg→Lys)。
应用DNAStar软件对Ile-139、Asn-226、Ile-324和Lys-382置换进行的抗原表位变化分析表明,这4处氨基酸残基置换都不会改变病毒的抗原表位。
将犬细小病毒抗原检测试剂盒与HA-HI和PCR方法进行了比较:犬细小病毒抗原检测试剂盒与HA-HI法比较,其敏感性、特异性和总符合率分别为100.0%、84.5%、90.8%;与PCR法比较,其敏感性、特异性和总符合率分别为85.3%、96.2%、90.0%。
这表明该试剂盒可以用于CPV 的流行病学调查。
CPV检测数据统计分析显示,2005、2006和2007年度CPV年检出率分别为24.14%、35.73%和25.52%;该病一年均可发生,但以第一和第四季度发病率较高;各年龄犬均可感染,但1-3月龄幼犬易感性最高。
关键词:犬细小病毒(CPV),VP2基因,序列分析,诊断方法,流行病学调查AbstractAt present, canine parvovirus (CPV) infection is one of most severe infectious diseases of domestic dogs. In order to understand the variation of CPV, we in this study amplified by PCR, sequenced and analyzed the VP2 gene of twenty faecal samples collected from dogs infected with CPV at different time from the year 2006 to 2007. In order to understand the epidemic situations of CPV infection, we on the base of evaluation of CPV Ag Test Kit, collected and analyzed the results of CPV detection of all dogs sent to China Agricultural University Animal Hospital from the year of 2005 to 2007, and whose clinical symptoms were vomiting and diarrhea, and vomiting or diarrhea. the results of these tests were as follow:The complete VP2 gene sequence was 1755bp encoding 585 amino acids. Sequence analysis of nucleotide and deduced amino acid residues revealed that nineteen samples were CPV-2a and one CPV-2b among the twenty canine parvovirus. All the samples had an amino acid substitution of residue 297 in VP2, Ser to Ala. nineteen CPV-2a samples studied in this study had substitution (IIe→Val) at residue 555 in VP2. Compared with classical CPV-2a/2b isolates, some samples had new amino acid substitutions: CPV/BJ005/07 and CPV/BJ008/07 at amino acid residue 139 in VP2 was Ile instead of Val; Ile-324 mutants accounted to 80% (16/20). Amino acid substitutions (Ser→Asn and Arg→Lys) of residue 226 and 382 were found in samples of CPV/BJ004/07 and CPV/BJ050/07, respectively. Four radical amino acid substitutions (Ile-139, Asn-226, Ile-324 and Lys-382 ) of VP2 did not change viral epitopes by DNAStar software analysis.The result of CPV detection of CPV Ag Test Kit was compared with those of HA-HI and PCR tests: It showed 100.0%, 84.5% and 90.8%, respectively in relative sensitivity, specificity and overall agreement between CPV Ag Test Kit and HA-HI, and 85.3%, 96.2% and 90.0 %, respectively as in comparison with PCR. The results indicated that CPV Ag Test Kit was a suitable test using in clinic and epidemiological survey.The results of CPV epidemiological survey displayed that the positive ratio of CPV infection was 24.14%, 35.73% and 25.52% in the year of 2005, 2006 and 2007 respectively. CPV infection of domestic dogs could take place through the year, but the highest infection rate was the first and fourth quarters. Domestic dogs of every years of age could be infected with CPV but puppies between 1-3 moths were more susceptivity than others.Key words:Canine parvovirus(CPV), VP2 gene, sequence analysis, diagnostic method, epidemiological survey目录第一章引言 (1)1.1 CPV感染研究进展 (1)1.1.1 病原学 (1)1.1.2 流行病学 (7)1.1.3 诊断方法 (7)1.1.4 预防 (14)1.2 研究意义与研究目标 (16)第二章北京地区犬细小病毒VP2基因序列分析 (17)2.1 材料 (17)2.2 方法 (17)2.3 结果 (19)2.4 讨论 (28)2.5 小结 (29)第三章犬细小病毒流行病学调查 (30)3.1 CPV抗原检测试剂盒临床应用评估 (30)3.1.1 材料 (30)3.1.2 方法 (31)3.1.3 结果 (33)3.1.4 讨论 (35)3.2 犬细小病毒流行病学调查 (37)3.2.1 材料 (37)3.2.2 方法 (37)3.2.3 结果 (37)3.2.4 讨论 (39)3.3 小结 (40)第四章结论 (41)参考文献 (42)致谢 (48)作者简介 (49)缩略词表缩写 英文名称 中文名称MVC Minute virus of canine 犬极细小病毒CDV Canine distemper virus 犬瘟热病毒DNA Deoxyribonucleicacid 脱氧核糖核酸pair 碱基对bp baseNS Non-structural-proteins 非结构蛋白protein 衣壳蛋白VP Capsidunit (基因)图距单位mu mapORFs open reading frames 开放阅读框g gram 克mRNA messenger ribonucleic acid 信使核糖核酸acid 多聚腺苷酸Poly(A) PolyadenylicÅ Å长度计量单位(1m=1010 Å) kDa kilodalton 千道尔顿CPV-2 Canine parvovirus type 2 犬细小病毒2型CPV-2a Canine parvovirus type 2a 犬细小病毒2a亚型CPV-2b Canine parvovirus type 2b 犬细小病毒2b亚型CPV-2c Canine parvovirus type 2c 犬细小病毒2c亚型virus 猫泛白细胞减少症病毒 FPV Felinepanleukopeniamin minute 分钟ml milliliter 毫升h hour 小时μL microliter 微升M mole/liter 摩尔/升CA V-2 Canine adenovirus type 2 犬腺病毒2型CPIV-2 Canine parainfluenza type 2 犬副流感病毒2型saline 磷酸盐缓冲盐水PBS phosphate-buffereds second 秒kidney(cell line)马-达二氏犬肾(细胞系)canineMDCK Madin-Darbyng nanogram 纳克minutes 转/分钟perr/min revolutionsnm nanometer 纳米MEV Mink enteritis virus 水貂肠炎病毒parvovirus 牛细小病毒BPV BovinePFU plaque forming unit 蚀斑形成单位triphosphates 三磷酸脱氧核苷dNTPs deoxy-ribonucleosideMcAbs monoclonalantibodies 单克隆抗体liter 微摩尔/升μM micromole/liter 毫摩尔/升mM millimole/第一章 引言1.1 CPV感染研究进展1978年,澳大利亚的Kelly和加拿大的Thomson等[1]同时从患肠炎的病犬粪便中分离获得的犬细小病毒(Canine parvovirus,CPV)。