鹌鹑源禽脑脊髓炎病毒的分离鉴定及遗传进化分析
Isolation,Identification and Phylogenetic Analysis of Avian Encephalomyelitis Virus Strain Isolated from Quail

为探究陕西省咸阳市某鹌鹑养殖厂的鹌鹑发病是否为禽脑脊髓炎病毒引起，采集发病鹌鹑的脑、肝脏、肠道等组织，通过鸡胚传代、RT-PCR扩增、免疫组织化学试验及动物回归试验对病原体进行分离鉴定，并对得到的序列进行同源性及遗传性分析。RT-PCR扩增结果显示，用禽脑脊髓炎病毒（AEV）特异性引物成功扩增得到大小为288 bp的目的片段，与参考株的核苷酸序列相似性及氨基酸序列相似性分别为84.9% ~99.3%和95.8%~98.9%；遗传进化分析结果表明，分离株与SX株位于同一分支；免疫组化试验结果显示，发病鹌鹑的脑、肝脏、肠道组织切片中存在大量的阳性棕黄色着色区域，而阴性对照没有；动物回归试验结果显示，攻毒组鹌鹑出现典型的禽脑脊髓炎（AE）临床症状，发病率55.1%，病死率100%，病理剖检发现患病鹌鹑的脑组织软化，脑半球轮廓模糊，对照组未见异常。成功分离得到1株鹌鹑源禽脑脊髓炎病毒，命名为AEV XY/Q-1410株，为鹌鹑禽脑脊髓炎的诊断及预防提供理论与技术支持。
In order to investigate the etiology of quail in a quail-breeding plant in Shaanxi province,the brain,liver and intestine tissues of the suspected quail were collected. Pathogens were isolated,identified and phylogenetic analyzed by Chicken embryo passage,RT-PCR amplification,Immunohistochemistry(IHC) and Animal regression test. RT-PCR results showed that a 288 bp fragment amplified by AEV-specific primers,which shared 84.9%-99.3% nucleotides similarity and 95.8%-98.9% deduced amino acid similarity with AEV reference strains; genetic evolution analysis showed that the strain was grouped into the same branch with SX strain; immunohistochemistry(IHC) assay showed that positive brown areas were observed in the brain,liver and intestine tissue sections in the incidence of quails,while no positive stains were observed in the negative control group. Animal regression assay showed that quails exhibited typical AE clinical symptoms in challenged group,meanwhile,the morbidity was 55.1% and the mortality was 100%. Pathological examination revealed that brain tissues of sick quails softening,cerebral hemisphere contour blurred,no clinical symptoms and pathological changes were observed in the control group. In conclusion,an AEV strain,named AEV XY/Q-1410 was successfully obtained from the sick quails,which provided the technical basis for the diagnosis and prevention of avian encephalomyelitis.