浙江省地方鸡种禽白血病毒抗原检测与部分分离株GP85基因序列分析

为了解浙江地区地方品种鸡中J亚群禽白血病病毒(subgroup J avian leukosis vrius,ALV-J)的感染情况与流行毒株的分子特征,对浙江省部分地方品种鸡体内ALV的p27抗原进行了检测,从疑似感染鸡群中检测分离到5株 ALV-J,并对其GP85基因进行PCR分子克隆和序列分析。研究结果显示:在检测的19个地方鸡品系中,所有品系的鸡样本都呈现抗原阳性,其中101系的抗体阳性率最高,母鸡阳性率为40.48%,公鸡阳性率为16.54%;126系次之,母鸡阳性率为28.87%,公鸡阳性率为3.30%;171系抗体阳性率最低,其母鸡阳性率仅为4.08%,公鸡的感染率为0。为了解地方鸡群中ALV-J的遗传变异,对分离到的5株ALV-J的GP85基因进行了分子克隆和序列分析。结果表明,5个分离毒株的GP85基因大小均为924 bp,与预期一致;本研究样品序列之间的核苷酸同源性为90.8%~98.5%,与原型毒株HPRS103核苷酸相似性为90.3%~97.0%,与国内其他分离株的同源性为86.5%~99.0%。分离株与福建(FJ201308株)和广东(WF13株)分离株的同源性最高。结果表明:浙江省大部分地方品种鸡都不同程度感染ALV-J,而且分离毒株已经发生了不同程度的变异,提示我们应加强浙江省地方品种鸡ALV的净化工作。

Detection of leukaemia virus antigen and analysis of GP85 gene sequence in local chicken breeds in Zhejiang Province

To investigate the infection of J subgroup avian leukosis virus (ALV-J)in local chicken breeds of Zhejiang Province, and to explore the molecular characterization of epidemic strains, infection of ALV-J was analyzed by detecting p27 antigen from samples collected from suspected infected chicken flocks of some area in Zhejiang Province. Five strains of ALV-J were isolated and GP85 genes were amplified by PCR and sequencing. Results demonstrated that ALV-J antigen positive occurred in all tested 19 lines of local chicken breeds, among of them, the positive rate of ALV p27 antigen was the highest in Line 101 and the positive rate was 40.48% in hen group, 16.54% in cock group; Line 126 took the second place, the positive rate was 28.87% in hen group, 3.30% in cock group; the positive rate was the lowest in Line171, the infection rate was 4.08% in hen group, and none was infected in cock group. Results of sequence determination and analysis demonstrated that GP85 amplified from 5 strains were all 924 bp in length, accord with the prediction; these sequences shared 90.8%-98.5% identification at nucleotide acid levels. The nucleotide similarity was 90.3%-97.0% with HPRS103, and 86.5%-99.0% with other domestic isolates. The isolates showed the highest homology with the isolates from Fujian FJ201308 strain and Guangdong WF13 strain. In conclusion, different lines of local chicken breeds in most parts of Zhejiang were infected with ALV-J to varying degrees, and the isolated strains showed different mutants to some extent, which suggested that the purification of ALV-J in Zhejiang Province should be strengthened.