高致病性FAdV-4传代中的毒力和Fiber2基因的比对分析  

Comparative analysis of virulence and Fiber2 gene in passage of highly pathogenic FAdV-4

作　　者：洪琴 邓翔飞 周香 徐彬 陈芳芳[1] HONG Qin;DENG Xiangfei;ZHOU Xiang;XU Bin;CHEN Fangfang(School of Animal Science and Technology,Anhui Agricultural University,Hefei 230036)

机构地区：[1]安徽农业大学动物科技学院,合肥230036

出　　处：《安徽农业大学学报》2023年第2期249-254,共6页Journal of Anhui Agricultural University

基　　金：安徽省教育厅重点项目(KJ2020A0124)资助。

摘　　要：为筛选禽腺病毒疫苗株和制备亚单位疫苗提供科学依据,探明高致病性禽腺病毒C亚型4血清型(FAdV-4)毒株在传代中的毒力变化以及不同感染方式对雏鸡死亡率的影响,首先制备2~15代的高致病性FAdV-4尿囊液,用LMH细胞检测第2、4、8和15代尿囊液的半数细胞感染量(TCID_(50));其次选取的4个代次尿囊液分别通过黏膜(点眼)和颈背部皮下途径接种SPF雏鸡,观察动物的死亡率;最后应用PCR方法扩增主要结构蛋白Fiber2基因序列并进行比对分析。结果表明:所有制备的2~15代FAdV-4毒株均在5~7 d内致鸡胚死亡(100%),4个代次毒株的TCID_(50)为10^(6.5±0.2)/0.1 mL,不同代次毒株间的毒力差异不显著(P>0.05);选取的4个代次毒株经颈背部皮下接种雏鸡的死亡率为100%,死亡雏鸡出现典型的心包积液综合征。而经黏膜接种的雏鸡死亡率呈下降趋势,分别为80%、50%、30%和30%;不同代次毒株Fiber2基因序列没有发生变化。总之,不同代次毒株通过皮下接种后对雏鸡的致病力没有差异,但黏膜接种的死亡率则逐代下降,而主要结构蛋白Fiber2基因则没有出现碱基变异。In order to provide a scientific basis for screening avian adenovirus vaccine strains and preparing subunit vaccines,and to investigate the virulence changes of highly pathogenic avian adenovirus C subtype 4 serotype(FAdV-4)strain in passage and the effects of different infection modes on chicken mortality.Firstly,the 2^(nd)-15^(th) generations of highly pathogenic FAdV-4 allantoic fluid were prepared,and LMH cells were used to detect the median tissue culture infective dose(TCID_(50))in the 2^(nd),4^(th),8^(th) and 15^(th) generations of allantoic fluid.Secondly,the SPF chickens were inoculated with allantoic fluid of four generations through the mucosal(eye drop)and cervical dorsal subcutaneous routes,respectively,to observe the mortality of the animals.Finally,the main structural protein Fiber2 gene sequence was amplified by PCR and compared.In this study,the 2^(nd)-15^(th) generations of FAdV-4 strains were prepared and all strains caused chicken embryo death within 5-7 days.The TCID_(50) of the four generations of FAdV-4 strains was 10^(6.5±0.2)/0.1 mL.There was no significant difference in virulence between different generations of FAdV-4 strains(P>0.05).The mortality rate of the selected four generations of strains inoculated subcutaneously through the neck and back was 100%,and the dead chickens showed typical hydropericardium syndrome.The mortality of chicks inoculated by mucous membrane decreased to 80%,50%,30% and 30%,respectively.The sequence of Fiber2 gene did not change in different generations.In summary,there was no difference in the pathogenicity of different generations of strains to chickens after subcutaneous inoculation,while the mortality of mucosal inoculation decreased generation by generation,and there was no base variation in the major structural protein Fiber2 gene.

关 键 词：强毒株FAdV-4 毒力 致病性 Fiber2 

分 类 号：S852.657[农业科学—基础兽医学]