鸡传染性支气管炎病毒LH2/01/10的分离鉴定

2001年在我国黑龙江省某鸡场疑似鸡传染性支气管炎的发病鸡群中，分离到一株病毒，将该病毒接种10日龄SPF鸡胚，取72h的尿囊液进行电镜观察并用1％胰酶处理，结果发现尿囊液中存在典型的冠状病毒，用胰酶处理过的尿囊液能凝集SPF鸡的红细胞，初步鉴定为鸡的传染性支气管炎病毒。将该病毒尿囊液再次接种10日龄SPF’鸡胚，通过病毒对鸡胚的致病作用、病毒超微形态特征以及病毒凝集鸡红细胞的特性等对该毒株进行研究，结果表明：经胰酶处理后的病毒尿囊液可凝集鸡红细胞。鸡胚的第二代病毒尿囊液(命名为LH2,／01／10)分别接种1日龄和15日龄的SPF鸡，发现对不同日龄的鸡表现不同的致病性，对1日龄接种鸡和同笼饲养的同居对照鸡致病力高，发病率为11／11，致死率分别为4／6和2／5；15日龄接种和同居感染鸡发病率为9／9，致死率分别为1／5和1／4。实验应用反转录一聚合酶链式反应技术对LH2／01／10的膜蛋白基因进行扩增、克隆和序列测定，结果表明该基因具有IBVM基因的共有分子特征．与IBV标准株M41的M基因核苷酸的同源性为90％，氨基酸的同源性为91％。这从分子水平进一步证实引起鸡群死亡的病毒为鸡传染性支气管炎病毒。

Isolation and identification of an avian infectious bronchitis virus strain LH2/01/10

A field strain of Infectious Bronchitis Virus (IBV) was isolated from immuned chicken trachea of the affected young layer. Biological characteristics of the virus were studied by virus pathogenicity to SPF chicken embryos and SPF chickens,morphological observation by electron-microscope and hemagglutination activity of virus to chicken red blood cells. It was demonstrated that the virus showed typical shape shared by members of Coronaviridae under electronic microscope and could hemagglutinate chicken red blood cells after treatment with 1 % trypsin. The gross lesions caused by the virus to SPF chicken embryos and SPF chickens were obvious. The morbidity of the second passage virus (LH2/01/10) to 1-day-old chickens was 11/11 and mortality was 4/6,2/5 to challenged chickens and chickens living in common and to 15-day-old chickens was 9/9 and 1/5,1/4 respectively. In addition, M gene of LH2/01/10 shared the typical molecular characteristics of all IBV M genes.