应用PCR及核苷酸序列分析技术对广西鸡传染性支气管炎病毒进行分子流行病学研究

Molecular epidemiology of avian infectious bronchitis viruses isolated in Guangxi by PCR and DNA sequencing technique

应用RT-PCR对9个传染性支气管炎病毒(in fection broch itis v irus,IBV)广西分离株的S1基因高变区Ⅰ(HVRⅠ)进行扩增和序列测定及分析,并用DNA star软件将这些分离毒株与我国常用疫苗毒株、国际上其它血清型的代表参考毒株分别进行核苷酸和氨基酸系统发生进化关系分析。核苷酸与氨基酸序列分析结果表明,这9个广西分离毒株可形成两个分支:第一分支与弱毒疫苗株H 120、H 52、M a5和参考株M 41、B eaudette的亲缘关系比较近,第二分支与疫苗株H 120、H 52、M a5的亲缘关系比较远。研究结果提示,广西养鸡业现场流行的IBV毒株已经发生了变异,实际免疫中要根据流行毒株的特性来生产和选择合适的疫苗。

S1 gene hypervariable regionⅠ （HVR Ⅰ ） of 9 strains of infectious bronchitis virus （IBV） isolated in Guangxi was amplified by using a RT-PCR technique and the cDNA sequences of those strains were determined. Phylogenetic relations based on the nucleotide and amino acid sequences were analyzed among Guangxi isolates and the reference strains in GenBank by using DNAstar software. The isolates could be divided into 2 groups： isolates in group I had close relationship with the traditional IBV vaccine strains H120, H52, Ma5 and reference strains M41 and Beaudette; isolates in group Ⅱ had less relationship with the vaccine strains. The results demonstrated that there has been gene variation happened in Guangxi field isolates of IBV, and the development and the applications of the vaccines should be based on the molecular characterization of the local strains.