鸭坦布苏病毒FJ42株的分离鉴定及其遗传进化分析  

Isolation, identification and genetic evolution analysis of duck Tambusu virus FJ42 strain

作　　者：郭晨 严萍 刘步期 田校源 吴异健[1,2] GUO Chen;YAN Ping;LIU Bu-qi;TIAN Xiao-yuan;WU Yi-jian(College of Animal Science,Fujian Agriculture and Forestry University,Fuzhou 350002,China;Fujian Key Laboratory of Traditional Chinese Veterinary Medicine and Animal Health(Fujian Agricultural and Forestry University),Fuzhou 350002,China;Fuzhou Dechuang Feed Co.,Ltd.,Fuzhou 350101,China)

机构地区：[1]福建农林大学动物科学学院,福建福州350002 [2]福建省兽医中药与动物保健重点实验室福建农林大学,福建福州350002 [3]福州德创饲料有限公司,福建福州350101

出　　处：《中国预防兽医学报》2021年第4期435-439,共5页Chinese Journal of Preventive Veterinary Medicine

基　　金：福建省自然科学基金(2017J01597);2020年福建农林大学校级大学生创新创业训练计划项目(202010389160);校科技创新专项基金项目(CXZX2017054)。

摘　　要：为了解福建地区鸭坦布苏病毒(DTMUV)的流行和遗传进化情况,本研究将2019年11月采集自福建某蛋鸭养殖场中经PCR检测为DTMUV阳性的病鸭卵巢组织样品处理后接种SPF鸡胚,盲传3代后收集尿囊液进行PCR检测和鸡红细胞凝集试验。将第3代尿囊液以1 mL/只的剂量接种200日龄产蛋鸭进行动物回归试验,分别于感染后6 d、9 d、15 d各剖杀3只鸭,观察其剖检病变,并采用PCR检测各组鸭卵巢组织中的DMUTV。对分离病毒的E基因经PCR扩增后测序,分析其编码氨基酸序列的同源性及遗传进化关系。结果显示:经病毒的分离、PCR鉴定及红细胞凝集试验结果表明,分离到一株DTMUV,将其命名为FJ42株;动物回归实验结果显示,实验组产蛋鸭出现了DTMUV感染的临床和剖检症状,且感染后6 d、9 d、15 d实验组鸭卵巢组织样品的PCR检测结果均为DTMUV阳性,而对照组鸭的PCR结果均为阴性,表明FJ42株对鸭的致病性较强。E基因编码氨基酸序列的同源性分析结果显示,鸭源分离株FJ42与马来西亚鸡源参考株同源性最高达98.1%~98.7%,而与我国参考株同源性较低,为95.8%~97.1%;E基因编码氨基酸序列的遗传进化树结果显示,FJ42株与马来西亚鸡源参考株位于同一小分支,而与我国鸭源参考株分属于不同的大分支;表明FJ42鸭源分离株很有可能是从马来西亚鸡源病毒变异而来。本研究首次在福建地区分离得到一株疑似马来西亚鸡源病毒变异而来的鸭源DTMUV,为探究福建地区DTMUV的遗传进化和流行病学研究提供了参考依据。In order to understand the prevalence and genetic evolution of duck Tambusu virus(DTMUV) in Fujian, ovarian tissue samples were collected from a local laying duck farm in November 2019 and the samples tested positive for DTMUV by PCR were generally treated and inoculated into specific-pathogen-free(SPF) chicken embryos. After the third blind passage, allantoic fluid was collected for PCR detection and hemagglutination assay. Besides, the allantoic fluid was inoculated into 200-day-old laying ducks at a dose of 1 m L/duck for animal regression test. Three ducks were killed on 6 th, 9 th, and 15 thdays after infection, respectively,for the observation of lesionsand detection of viral load in ovarian tissue using PCR. The E gene of the isolated virus was amplified by PCR and sequenced, and the homology and genetic evolution of the encoded amino acid sequence were analyzed. The results of virus isolation, PCR and hemagglutination tests identified the isolate as DTMUV and the isolate’s was named as FJ42. The results of animal regression experiment showed that the laying ducks in the inoculated group had the clinical and necropsy symptoms of DTMUV infection, and the corresponding ovarian tissue samples were positive for DTMUV on 6 th, 9 th, and 15 thdays after infection as assayed by PCR test. While all samples of control group were negative positive for DTMUV. These findings suggest that FJ42 was relatively highly pathogenic to ducks. Homology analysis of amino acid sequences encoded by E gene showed that the FJ42 duckderived strain had the highest homology with Malaysian reference strains(98.1% to 98.7%) but low homology with Chinese reference strains(95.8% to 97.1%). Phylogenetic analysis of the amino acid sequences revealed that FJ42 was in the same branch with the Malaysian duck-derived reference strains but distinctively separated from the Chinese duck-derived reference strains. These results indicated that FJ42 was most probably originated from a Malaysian chicken-derived strain. In this study, a duck-derived

关 键 词：鸭坦布苏病毒 E基因 遗传进化 分离鉴定 

分 类 号：S852.65[农业科学—基础兽医学]