【摘要】 为了解福建省番鸭呼肠孤病毒（Muscovy duck reovirus,MDRV）的生物学特性及其遗传变异情况,2021—2022年从福建省番鸭集中饲养区,收集疑似MDRV感染临床病例的病料样品125份,进行MDRV病原学检测以及MDRV病原分离、攻毒试验、疫苗免疫攻毒试验和S4基因序列分析。结果显示:在115份免疫过MDRV活疫苗的临床病例病料中未检测到MDRV阳性,在10份未免疫MDRV活疫苗的临床病例病料中,检出6份MDRV阳性;从阳性病料中分离出的6株MDRV毒株均能致死番鸭胚,对雏番鸭的致病率为60%～100%,致死率为40%～60%;对1日龄番鸭免疫MDRV活疫苗后,在7日龄时进行分离毒株攻毒试验,未见番鸭发病死亡;6株MDRV分离毒株S4基因核苷酸序列的同源性大于99%,与1997年流行株MDRV-MW9710同源性为98.6%～99.4%,属于同一分支。结果表明:MDRV在福建省番鸭群中依然存在,对未免疫番鸭群的致病性较高,其致病性和S4基因序列特性与最初流行毒株变化不大,当前疫苗仍可有效预防MDRV感染,因此要重视MDRV活疫苗的免疫。更多还原

【Abstract】 In order to investigate the biological characteristics and genetic variation of Muscovy duck reovirus(MDRV)prevalent in Fujian Province,125 clinical samples were collected from the cases suspected of MDRV infection in the centralized breeding area of Muscovy ducks in Fujian Province from 2021 to 2022 for pathogen detection,isolation,challenge test as well as vaccine challenge test and S4 gene sequence analysis.The results revealed that no MDRV was detected from 115 cases immunized with live MDRV vaccine,and 6 out of 10 cases without vaccination were MDRV positive.All 6 isolates of MDRV from the positive cases could make Muscovy duck embryos die,with a pathogenicity rate ranged from 60% to 100%,and a mortality rate from 40% to 60% for young Muscovy ducks.1-day-old Muscovy ducks were vaccinated with MDRV live vaccine,and challenge test was conducted when they were at 7-day old,none of them infected or died.The homology of S4 gene nucleotide sequences of the isolates was above 99%, which was98.6% to 99.4% identity to the MDRV-MW9710 strain prevalent in 1997,locating at the same branch.In conclusion,MDRV was still prevalent in Muscovy duck population in Fujian Province, with a high pathogenicity to the ducks without vaccination,its pathogenicity and S4 gene sequence characteristics remained almost the same as those of the initial epidemic strain,so current vaccine could be used to effectively prevent such infection,indicating a priority to immunization with MDRV live vaccines.更多还原