Infectivity in the ileum of cattle challenged orally with bovine spongiform encephalopathy
Infectivity in the ileum of cattle challenged orally with bovine spongiform encephalopathy
复制标题
经口患牛海绵状脑病的牛回肠的感染性
DOI：
10.1136/vr.135.2.40
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发表时间：
1994
影响因子：
2.2
通讯作者：
MW Horigan
中科院分区：
文献类型：
--
作者：
G. Wells;M. Dawson;Sa Hawkins;RB Green;I. Dexter;Meunier Francis;M. Simmons;Arieyeh J Austin;MW Horigan
40头4月龄黑白花奶牛/荷斯坦小牛（出生于1991年，来自无牛海绵状脑病（BSE）的农场）经口给予100 g来自75例BSE确诊病例的合并脑干匀浆。10头小牛未接受治疗，作为对照。对所有牛进行临床监测。从6月龄开始，此后每隔4个月，处死3头攻毒小牛和1头对照小牛，采集组织进行感染性试验和组织病理学检查。将单个组织合并液和对照组织接种至小鼠体内，进行感染性的标准定性试验。7组已被处死，在这些牛或存活牛（接种后30个月）中未观察到BSE的临床证据。从接种后6个月和10个月处死的攻毒小牛远端回肠的小鼠试验中获得了BSE经口实验传播给牛的证据，但从接种后2个月处死的小牛中未获得。该研究仍在继续，但报告的观察结果可能提供有关BSE发病机制的信息，特别是关于进入中枢神经系统之前发生感染的信息。
Forty 4-month-old Friesian/Holstein calves, born in 1991, from farms free of bovine spongiform encephalopathy (BSE) were dosed orally with 100 g of homogenate of pooled brain stems from 75 cases confirmed cases of BSE. 10 calves received no treatment and acted as controls. All cattle were clinically monitored. Starting at 6 months old and thereafter at 4-month intervals, 3 challenged and one control calf were killed and tissues collected for infectivity assays and histopathological examination. Single tissue pools and control tissue were inoculated into mice for standard qualitative assay of infectivity. 7 groups had already been killed and no clinical evidence of BSE has been seen in these or the surviving cattle (30 months after inoculation). Evidence of oral experimental transmission of BSE to the cattle has been obtained from the mouse assay of the distal ileum from challenged calves killed 6 and 10 months after inoculation but not from those killed 2 months after inoculation. The study is continuing but the observations reported may provide information on the pathogenesis of BSE particularly regarding the development of infection before entry to the central nervous system.