带有REV-LTR片段的马立克氏病病毒重组野毒株与超强毒株致病性和横向传播性比较  

Comparision of pathogenicity and horizontal transmission ability between recombinant Marek's disease virus field strain with REV-LTR and a very virulent reference strain

作　　者：许晓云[1] 孙爱军[1] 崔言顺[1] 崔治中[1] 

机构地区：[1]山东农业大学动物科技学院,泰安271018

出　　处：《微生物学报》2009年第4期540-543,共4页Acta Microbiologica Sinica

基　　金：国家自然科学基金项目(30671571)~~

摘　　要：【目的】GX0101是一株插入了禽网状内皮组织增生症病病毒(REV)-LTR片段的马立克氏病病毒(MDV)重组野毒株,本文将其致病性、致肿瘤性和横向传播能力与超强毒参考株(vvMd5)进行比较。【方法】利用MDV特异性核酸探针对同罩饲养的对照鸡的羽毛囊DNA进行检测。【结果】在经抗MDV疫苗免疫的SPF鸡攻毒试验中表明,GX0101株的致死率28.6%和致肿瘤率7.1%均低于超强毒参考株Md5的致死率63.1%和致肿瘤率19.0%。但是,利用MDV特异性核酸探针对同罩饲养的对照鸡的羽毛囊DNA检测表明,GX0101从攻毒后第28天就有6/15的比例从羽毛囊中检出MDV,而与vvMd5接种鸡同一隔离罩的对照鸡,在35d时才在2/14的个体中检出MDV,即GX0101的横向传播能力大于超强毒株。这一结果表明,MDV的致病性不一定与横向传播力相平行。【结论】由此推测,显著增高的横向传播能力可能就是这一整合进REV-LTR的重组病毒株能在鸡群中逐渐流行开来的选择性竞争优势之一。[ Objective] GX0101 is a recombinant field strain of Marek＇s disease virus （MDV） with a long terminal repeat （LTR） insert from reticuloendotheliosis virus, a chicken retrovirus. In this study, GX0101 strain was compared to a very virulent reference strain Md5 for their pathogenicity and transmission ability. [ Methods] MDV genomic DNA in feather tips was tested and compared by dot blot hybridization with MDV specific probe in control chickens kept in the same isolators in which chickens were challenged with GX0101 or MdS. [Results] mortality and tumor rates of GX0101 were 28.6% and 7.1% for SPF chickens viccinated against Marek＇s disease virus. Mortality and tumor rates of vvMd5 were 63.1% and 19.0% in the same viccinated SPF chickens. Mortality and tumor rates of GX0101 were lower than that of vvMd5. However, horizontal transmission ability of GX0101 was stronger than that of Md5. After 28 days challenged by GX0101, MDV was detected in 6 of 15 samples, after 35 days challenged by vvMdS, MDV was detected in 2 of 14 samples. [ Conclusion] Horizontal transmission ability of MDV isolates was not necessarily parallel to their pathogenicity. It is suggesting that the increased horizontal transmission may be one of selective competitive advantages. Such advantages may help recombinant viruses with the LTR-insert become more and more popular gradually in chicken flocks.

关 键 词：马立克氏病毒 重组病毒 致病性 横向传播 斑点杂交 

分 类 号：S852.65[农业科学—基础兽医学]