2011年～2012年四川地区J亚型禽白血病分子流行病学调查

Molecular epidemiology of subgroup J avian leukosis virus from Sichuan area during 2011 to 2012

为了解2011年～2012年四川地区J亚型禽白血病病毒（ALV-J）流行情况及流行病毒株的分子特征,本研究采集四川地区疑似禽白血病的病料样品784份（血液样品700份,组织样品84份）进行PCR检测,并对部分样品的gp85基因进行序列测定和分析.血液样品和组织样品ALV-J检出率分别为3.1％ （22/700）和14.3％（12/84）.核苷酸序列比对结果表明,18个阳性样品的gp85基因核苷酸同源性为87.7％～99.8％,与ALV-J株HPRS-103的核苷酸同源性为87.3％～98.2％,与以前分离的J亚群四川株SCGS-1的核苷酸序列同源性为87.9％～94.4％.遗传进化分析表明,18个样品分别属于不同的分支,其中来自石棉的样品SM与其他样品的遗传距离最远.该调查结果显示四川地区鸡场的ALV-J感染比较普遍,其gp85基因存在明显的遗传多样性,引种是导致这种遗传多样性的重要原因.

To investigate the epidemiology of subgroup J avian leukosis （ALV-J） in Sichuan area, a total of 784 samples were collected from 8 chicken farms and detected by PCR with ALV-J gp85 gene specific primers. The results showed that 34 （4.3%） samples were positive for ALV-J, including 22 （3.1%） blood samples and 12 （14.2%） tissue samples. The nucleotide homologies of those 18 positive samples were 87.7% to 99.8%, of which the nucleotide homologies were 87.3% to 98.2% for HPRS-103 strain and 87.9% to 94.4% for SCGS-1 strain. Phylogenetic analysis showed that the 18 samples belong to different genetic branch, and the sample SM from Shimian country had the longest genetic distance to other samples. In conclusion, ALV-J infection was common in Sichuan area, and a relatively big genetic diversity was detected in the gp85 gene of ALV-J positive samples, which could be related to the introduction of chickens from other provinces.