Abstract:
Chronic wasting disease (CWD) is a fatal prion disease of cervids that has spread across much of North America. Although gold standard CWD diagnostics involve postmortem testing of medial retropharyngeal lymph nodes or obex (brain stem), a key tissue sample for antemortem testing is rectoanal mucosa-associated lymphoid tissue (RAMALT). However, collection of an adequate sample (i.e., enough lymphoid follicles) may be affected by factors such as deer age, repeated sampling, skill of the sampler, and adverse conditions during collection. Here, we document the protocol used to train personnel for RAMALT collection in a large study of free-ranging white-tailed deer (Odocoileus virginianus) in Wisconsin, USA, and determine factors that contributed to the occurrence of inadequate RAMALT samples. Our training protocol included hands-on experience with postmortem tissues, as well as a mentored collection process in the field. Collection of RAMALT under field conditions was highly successful, with 763/806 (94.7%) samples deemed adequate for subsequent testing. Although inadequate samples were rare, they were more likely to occur with older deer and when samples were collected at dusk (i.e., limited ambient lighting). We conclude that RAMALT collection can be highly successful under adverse field conditions, including with technicians with limited prior veterinary experience, and we provide details of our training program to facilitate repeatability in other antemortem CWD testing efforts.
摘要:
慢性消耗性疾病(CWD)是一种致命的宫颈朊病毒病,已在北美大部分地区蔓延。尽管金标准CWD诊断涉及咽后内侧淋巴结或obex(脑干)的尸检,临死前检测的关键组织样本是直肠肛门粘膜相关淋巴样组织(RAMALT).然而,收集足够的样本(即,足够的淋巴滤泡)可能会受到鹿年龄等因素的影响,重复采样,采样器的技能,和收集过程中的不利条件。这里,我们记录了用于在威斯康星州对自由放养的白尾鹿(Odocoileusvirginianus)进行大规模研究的RAMALT收集培训人员的协议,美国,并确定导致RAMALT样品不足的因素。我们的培训方案包括死后组织的实践经验,以及该领域的指导收集过程。在野外条件下收集RAMALT非常成功,763/806(94.7%)个样本被认为足以进行后续测试。尽管样本不足很少见,它们更有可能发生在老鹿身上,以及在黄昏收集样本时(即,有限的环境照明)。我们得出的结论是,在不利的野外条件下,RAMALT收集可以非常成功,包括先前兽医经验有限的技术人员,我们提供培训计划的详细信息,以促进其他临终CWD测试工作的可重复性。