两株不同疾病型鸭呼肠孤病毒部分生物学特性的比较

Comparison of Biological Characteristics of Two Different Disease-type Duck Reovirus(MDRV and NDRV)

通过电镜观察、血清交叉中和试验、病毒的细胞病变特征、病毒基因组特征及S3蛋白基因分析等方法,比较2株不同疾病型鸭源呼肠孤病毒的生物学及基因组特性差异。染毒细胞的超薄切片观察结果表明,2种病毒为球形,直径约70nm,新型鸭呼肠孤病毒(NDRV)在胞浆中呈晶格状分布,而番鸭呼肠孤病毒(MDRV)呈零星、散在分布;MDRV和NDRV之间的相关系数R值很小,抗原相关性较低;NDRV的细胞病变类型以巨融合为主,而MDRV则以细胞圆缩、坏死为主;经尿囊腔接种,NDRV能致死鸡胚,而MDRV不能致死鸡胚。MDRV及NDRV的S基因片段的迁移率明显不同;两者S3基因处在不同的进化分支。结果初步表明不同疾病型的水禽呼肠孤病毒MDRV和NDRV的生物学特性有较大差异。

Muscovy duck reovirus （MDRV） and Novel duck reovirus （NDRV）, which belong to Orthoreovirus, are important pathogens of waterfowl. This study was conducted to compare the biological characteristics of MDRV and NDRV. Several methods were undertaken such as ultrathin sections observation, cross virus-neutralization test, the pathogenicity to avian embryos and cell lines, comparison of genome segment profiles and the characteristics analysis of $3 gene. The results of ultrathin sections observation showed that MDRV and NDRV viral particles were spherical and the diameter was both about 70 nm. MDRV scattered in MDEF cytoplasm, whereas NDRV particles arranged in crystal lattice. Relatedness （R） values showed that the antigen of the two viruses were generally different. MDRV＇s CPE feature was cell rounding, while which of NDRV was cell fusion. NDRV induced the death of 9-day-old chicken embryos, whereas MDRV did not. The migration profiles of NDRV and MDRV genome segments were different. The S3 genes of the two viruses were at different branches of molecular phylogenetic tree. In conclusion, the biological characteristics of MDRV and NDRV were obviously different.