[Objective] To examine the integration of reticuloendotheliosis virus (REV) gene in FPV genome, and to study on the changes of the specific antibody against REV in FP flocks, the cytopathic effect in tissue cells infected by FPV and the histopathological changes in FP chickens. [Method] Fowlpox viruses (FPV) were isolated from 9 typical fowlpox (FP) clinical cases identified in Taian and surrounding areas, using PCR to amplify REV-env, LTR sequence, ELISA to test the changes of the specific antibody against REV in FP flocks, electron microscopy to observe the morphous of FPV, and histopathological examination of FP chickens. [Result] The results showed that all of the 9 FPV isolates were integrated with REV gene, the tight sphere of the nucleus in infected tissue cells transformed into helix pattern, antibody levels against REV in FP chickens increased significantly. Besides the common pathological changes caused by FP, severe atrophy of spleen, thymus, Bursa, reticuloendothelial cell proliferation, pathologic changes of liver, duodenum and lung were also found. The results of SPF chickens experimental infection by separated and purified FPV showed that the changes of antibody against REV and pathological changes of organs during the healing stage were identified as the changes caused by wild virus. [Conclusion] In summary, integration of FPV with REV gene is common in chickens from Taian and surrounding areas, and the pathogenicity of the wild FPV strains integrated with REV gene has changed to some extent.%[目的]验证FPV野毒株是否存在REV基因整合现象,初步研究整合毒株致病鸡群REV的抗体变化规律、FPV感染组织细胞的病变及发病鸡的病理组织学变化特征.[方法]自泰安及周边地区搜集的9例典型FP临床病例取其病变组织分离FPV,电镜观察FPV形态特征、PCR扩增REV-env和LTR序列、ELISA检测FP发病鸡群血清REV抗体变化特征及病理组织学检查病鸡的病理学变化.[结果]9株FPV野毒株均有REV基因片段的整合,整合毒株使感染组织细胞的核由原来紧密球状变成较松散的螺旋状;FP患病鸡REV抗体阳性率显著升高;发病鸡除FP的一般病变外,同时显示脾脏、胸腺、法氏囊等免疫器官的淋巴组织严重萎缩,网状内皮细胞增生;肝脏、十二指肠、肺脏等器官内的淋巴组织亦表现相应的病理变化;用分离纯化整合REV基因的FPV毒株对SPF鸡试验性感染表明:整合REV基因的FPV毒株试验性感染SPF鸡患痘后期REV抗体水平的变化及组织器官的病理变化与野毒株FPV自然感染鸡所致病变相同.[结论]泰安及周边地区流行的FPV野毒株普遍存在REV基因的整合现象,整合有REV基因的FPV野毒株的致病性已发生改变,具有REV的某些致病特征.
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