NDV山东分离株的生物学特性及其HN基因的克隆与序列分析

Biological Characteristics of One Strain of Newcastle Disease Virus and Sequence Analysis of HN Gene

2004年从山东某鸡场发病蛋鸡群中分离到一株新城疫病毒（编号：ShD-2-04），对其生物学特性进行了研究，并对其HN基因进行了克隆和序列分析。结果表明：该病毒的最小致死量病毒致死鸡胚的平均时间（MDT）为50．4，1日龄SPF鸡脑内接种分离病毒致病指数（ICPI）为1．85，6周龄SPF鸡静脉接种致病指数（IVPI）为2．42，表明该病毒具有新城疫强毒株的一些特征；其HN基因开放性阅读框架（ORF）为1，716bp，编码571个氨基酸；与国外发表的部分新城疫病毒强毒株和弱毒株之间相应序列进行比较，核苷酸序列的同源性在81．6％-87．2％之间，氨基酸同源性在87．6％-90．7％之间。

The biological characteristics of one strain of newcastle disease virus （NDV） isolated from chickens in Shandong in 2004 were studied. Its haemagglutinin-neuraminidase （HN） gene was cloned and analyzed. The resuits showed that： MDT, ICPI and IVPI are 50. 4, 1.85 and 2. 42 respectively. It means that the isolated virus belongs to virulent strain. Its HN gene has an opening reading fragment （ORF） of 1, 716 bp and it encodes 571 amino acids, Compared with the published virulent strains and aviruient ones of NDV, the homology of the nucleotide of HN gene is 81.6% - 87. 2% and the homology of the deduced amino acids sequences of HN gene is 87.6% -90. 7%.