2008—2012年山东省鸡传染性支气管炎病毒遗传演化分析和致病性研究  

Phylogenetic Analysis and Pathogenicity of Infectious Bronchitis Viruses Isolated in Shandong Province during 2008-2012

作　　者：胡北侠[1,2] 杨少华[2] 许传田[2] 张伟[2] 张琳[2] 黄庆华[2] 张秀美[2] 黄艳艳[2] 文心田[1] 

机构地区：[1]四川农业大学动物医学院,雅安625014 [2]山东省农业科学院畜牧兽医研究所,山东省畜禽疫病防治与繁育重点实验室,济南250100

出　　处：《畜牧兽医学报》2014年第5期795-801,共7页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：山东省自然基金(ZR2009DQ015);现代农业产业技术体系建设专项资金(CARS-42-Z12)

摘　　要：本研究目的在于进一步明确山东省鸡传染性支气管炎病毒(infectious bronchitis virus,IBV)的流行病学和遗传演化规律。自2008—2012年从山东省发病鸡群中分离鉴定了20株IBV,并对其S1、N和M基因进行序列测定分析。在此基础上,选择3个代表性IBV流行株进行了致病性评价。结果显示:根据S1基因绘制的遗传进化树显示,20个IBV分离株和参考株形成4个进化分支。18个IBV分离株属于以QXIBV为代表的基因Ⅰ型,CK/CH/SD09/005和SDIB781/2012两个分离株与参考株形成独立的进化分支———基因Ⅳ型,与其它3个基因型IBV相似性仅为65.1%~67.1%。N基因和M基因序列分析结果显示,基因Ⅳ型分离株CK/CH/SD09/005和SDIB781/2012 N和M基因相似性仅为86.7%和87.9%,而SDIB781/2012 N和M基因分别与QX基因型分离株SDIB764/2012和SDIB702/2012 100%相似,表明2个基因型IBV流行株之间发生了基因重组。致病性试验结果显示,QX基因型分离株SDZB0808、SDIB821/2012和基因Ⅳ型分离株CK/CH/SD09/005对18日龄SPF鸡的致死率为60%~70%,病死鸡主要表现肾肿大和大量白色尿酸盐沉积于心、肾等器官表面,临床症状和病理变化基本一致。研究结果显示,山东省近年来IBV流行株优势基因型为QX,同时出现新型IBV流行株,2个基因型IBV均属于肾型传支。2个基因型IBV流行株之间通过基因重组不断进化,提示必须对IBV进行持续性的流行病学监测。The aim of this study was to further determine the evolution and epidemiological situation of infectious bronchitis virus(IBV)in Shandong Province.The S1,Nand Mgenes of twenty IBV strains isolated from diseased chickens in Shandong Province between 2008and 2012were sequenced.Besides,the pathogenicity of three isolates was evaluated in 18-day-old specific-pathogenfree(SPF)chickens.Phylogenetic analysis based on the S1genes(1 611bp)revealed that 20IBV isolates and reference strains were grouped into four distinct clusters(genotypes).Eighteen IBV isolates belonged to the QX genotype.Two isolates,CK/CH/SD09/005and SDIB781/2012weretyped into a separate cluster—genotypeⅣ and showed only 65.1%-67.1% nucleotide identities to IBVs of the other three genotypes.CK/CH/SD09/005and SDIB781/2012showed nucleotide identities of 97.8%in S1gene while they shared only 86.7%and 87.9% nucleotide identities in the Nand Mgenes,respectively.SDIB781/2012had nucleotide identities of 100% with SDIB764/ 2012and SDIB702/2012(QX-like)in N and M genes,respectively,which indicated genetic recombinations between strains of QX-like and gentotype Ⅳ.In the challenge test,SDZB0808, SDIB821/2012and CK/CH/SD09/005resulted in deaths of 60%-70%in experimental infections of SPF chickens.Swollen speckled kidneys and distended ureters filled with uric acid were observed in dead birds.Besides,plenty of uric acid salt deposited on the surface of kidney,heart and other tissues of infected birds.There is no significant distinction in clinical and pathological changes of birds inoculated with three IBV strains.The results showed that the QX-like strains,the predominant type IBV,and a new genotype IBV had been co-circulating in Shandong Province in recent years.Both of them are Nephropathogenic strains.The recombinant events between IBV strains of QX and the new genotype emphasize the importance of a persistent survey of IBV field strains.

关 键 词：鸡传染性支气管炎病毒 遗传演化 基因型 致病性 

分 类 号：S858.31[农业科学—临床兽医学]