贵州省禽白血病病毒J亚群感染的血清学检测与PCR鉴定

Serological detection and PCR identification of avian leukosis virus subgroup J infection in Guizhou Province

采用禽白血病J亚群抗体检测试剂盒对8个鸡场的血清样本进行了检测,并对出现肿瘤病变的病死鸡进行了病理组织学检查;同时采集16份禽白血病病毒J亚群(ALV-J)抗体阳性鸡的血液或肝组织,提取DNA样本进行PCR扩增,并测序分析。结果显示,4个肉种鸡场的ALV-J抗体阳性率平均为16.52%(3.33%～30.0%),而4个蛋种鸡场的ALV-J抗体阳性率均为0。病理组织学观察可见,在肝、肾、脾组织中出现大量增生的、含嗜酸性颗粒的髓细胞样瘤细胞。PCR检测发现,有14份样本扩增出ALV-J亚群特异性的病原核酸片段(545 bp),检出率达87.5%,其中在3份肝样本中同时扩增出ALV-A亚群特异性的病原核酸片段(691 bp);而ALV-J抗体阴性鸡、淋巴细胞性白血病和血管瘤型白血病的20份样本均未扩增出545 bp片段。扩增出的545 bp片段与ALV-J亚群毒株HPRS-103和ADOL-HcL的相应核苷酸序列的同源性分别达96.2%～96.8%和95.5%～96.8%。结果证实,贵州省鸡群中确实存在ALV-J亚群感染和骨髓细胞瘤病,且出现A亚群、J亚群混合感染的情况。

The serum samples collected from 4 broiler farms and 4 layer farms were detected by using avian leukosis virus subgroup J（ALV-J） antibody Kit. The sick or dead chickens manifesting tumor lesions in visceral organs were histopathologically examined. 16 DNA samples were extracted from blood or liver of the positive chickens with ALV-J antibody,amplified by PCR and sequenced. The mean of ALV-J antibody positive rate was 16.52% in the 4 broiler flocks and was 0 in the 4 layer farms. A lot of myelocyte-like tumor cells filled with acidophilus granules were observed in the liver, kidney and spleen tissues, respectively. The specific fragment of 545 bp for ALV-J was amplified from 14 DNA samples,accounting for 87.5% （14/16） ,and a specific fragment of 691 bp for ALV-A was amplified from 3 liver samples. No fragment was amplified from 20 DNA samples prepared from the ALV-J antibody-negative chickens,and the lymphoid leukosis and hemangioma cases. The amplified 545 bp fragment shared 96.2%- 96.8% and 95.5 %- 96. 80% identities in nucleotide with that of HPRS-103 and ADOL-HcL strains of ALV-J ,respectively. The resuits of serology, histopathology and molecular biology,definitely demonstrated that ALV-J infection,coinfection of ALV-J with ALV-A,and avian myelocytomatosis were prevalence in chicken flocks in Guizhou Province.