摘要
本研究从广东省某发病番鸭场分离得到的呼肠孤病毒(DRV)混合有番鸭细小病毒(MDPV)疫苗株。采用MDPV阳性血清中和后,经2轮番鸭胚有限稀释克隆获得纯化的DRV。电镜观察病毒粒子呈球形、无囊膜、双层衣壳、直径约70 nm。F6代病毒滴度为log107.5TCID50/0.1 mL,病毒能够致番鸭胚成纤维细胞产生细胞病变,并能够致死番鸭胚和SPF鸡胚,回归1日龄雏番鸭出现典型的肝脏点状或斑块状出血等特征性病变,与临床发病鸭相同。分离株S3基因核苷酸同源性与太湖流域2011年分离株DRV-TH11最高,为99.9%,与福建番鸭源分离株MDRV-J18为98%;与早期MDRV在66.8%～67.2%之间,处于不同进化分支上。本研究分离株对番鸭胚、SPF鸡胚及雏番鸭致病力强,而且其基因序列比早期分离株变异较大,应加强监测并及时筛选新疫苗株以有效防控该病的发生和蔓延。
A duck reovirus （DRV） was isolated from vaccinated Muscovy ducks, which administrated with Muscovy duck reovirus vaccine and Muscovy duck parvovirus （MDPV） vaccines in Guangdong province, and purified by limited dilutions in Muscovy duck embryonated eggs from the affected duck tissue sample pre-treated with polyclonal antibody against MDPV. Electron microscopy examination showed that the isolate exhibited typical morphological characters of DRV. The isolate cause the death of 9- to 11-day old of Muscovy duck embryos and SPF chicken embryos in 96 hours post infection. The virus titer at 6th passage was logl075 TCID50/0.1 mL. Infection of day-old Muscovy ducks with the isolate reproduced typical clinical signs and pathological lesions seen in the original sick ducks. Sequence analysis of the isolate showed that the $3 gene was 99.9% homology with that of DRV-TH11 isolated from Taihu area in 2011, whereas it only shared 66.7% to 67.2% identity with those of Muscovy DRV isolated earlier. The isolate clustered at the same clade with those DRV isolated in recent years, while the classical Muscovy DRV clustered in a distant lineage on phylogenetic analysis. These results highlight the necessity of monitoring the virus prevalence in duck, and development of new candidate vaccines for effective prevention of the diseases.
出处
《中国预防兽医学报》
CAS
CSCD
北大核心
2013年第8期618-622,共5页
Chinese Journal of Preventive Veterinary Medicine
基金
广东省产学研项目(2010B090301019)
关键词
番鸭
呼肠孤病毒
分离
电镜
特性
Muscovy duck
reovirus
isolation
electron microscopy
characterization
