鸭坦布苏病毒江苏XZ株的分离和鉴定

Isolation and Identification of Duck-origin Tembusu Virus Jiangsu XZ Strain

从江苏徐州地区分离到的以引起樱桃谷鸭产蛋下降和死亡为特征的1株病毒，命名为XZ株。对该病毒进行电镜观察、血凝试验、ELD50测定、RT—PCR扩增特异性目的基因、序列比对分析和动物回归试验。结果显示，分离毒株能致死鸭胚和鸡胚，电镜下观察到球形病毒粒子，不具有血凝性，对病料和接毒鸭胚尿囊液进行RT—PCR，均可扩增出基因片段，其核苷酸序列与坦布苏病毒奉贤株的相似性最高，为98．7％，与其他坦布苏病毒的毒株也具较高同源性，为86％～98％。用鸭胚分离毒株接种健康产蛋鸭，能复制出同样的疾病。结果表明分离病毒为鸭黄病毒属的坦布苏病毒。

A new virus named XZ strain, was isolated from layer cherry duck flocks with typical eggs drop symptoms and death in Xuzhou district of Jiangsu province. The virus was observed by scanning electron microscope, hemagglutination test, ELD50 measurement, amplification specific DNA by RT-PCR, sequence analysis and animal regression experiment. The results showed that the isolated virus caused lethal hemorrhage in SPF chicken embryo and duck embryo. The appearance of virus particles showed spherical under election-microscope, and the virus had no hemagglutinating activity. The samples from infected ducks and the allantoie fluid of infected duck embryos were PCR positive for duck flavivirus. Sequence analysis to the gene frag- ment of the isolated virus revealed 98.7% nucleotides identity with Tembumu virus Fengxian strain, and had high homology- with other Ternbumu virus strains from 86% to 98%. Experimental infections with the isolated virus resulted in reproduction of the disease in healthy egg laying duck. The results demonstrated that the isolated virus was Tembumu virus of duck . flavivirus.