Scrapie is a naturally occurring transmissible spongiform encephalopathy (TSE) that affects sheep and goats. Sheep and goats can be infected with scrapie as lambs or kids via contact with the placenta or placental fluids, or from ingestion of prions shed in the environment and/or bodily fluids (e.g., saliva, urine, and feces). Like other TSEs, scrapie is generally not diagnosed before extensive and irreversible brain damage has occurred. Therefore, a reliable method to screen animals may facilitate diagnosis. Additionally, while natural scrapie in sheep has been widely described, naturally acquired goat scrapie is less well-characterized. The purpose of this study was to better understand natural goat scrapie in regard to disease phenotype (i.e., incubation period, clinical signs, neuroanatomical deposition patterns of PrP^Sc, and molecular profile as detected by Western blot) and to evaluate the efficacy of antemortem tests to detect scrapie-positive animals in a herd of goats. Briefly, 28 scrapie-exposed goats were removed from a farm depopulated due to previous diagnoses of scrapie on the premises and observed daily for 30 months. Over the course of the observation period, antemortem biopsies of recto-anal mucosa-associated lymphoid tissue (RAMALT) were taken and tested using immunohistochemistry and real-time quaking-induced conversion (RT-QuIC), and retinal thickness was measured in vivo using optical coherence tomography (OCT). Following the observation period, immunohistochemistry and Western blot were performed to assess neuroanatomical deposition patterns of PrP^Sc and molecular profile. Our results demonstrate that antemortem rectal biopsy was 77% effective in identifying goats naturally infected with scrapie and that a positive antemortem rectal biopsy was associated with the presence of clinical signs of neurologic disease and a positive dam status. We report that changes in retinal thickness are not detectable over the course of the observation period in goats naturally infected with scrapie. Finally, our results indicate that the accumulation of PrP^Sc in central nervous system (CNS) and non-CNS tissues is consistent with previous reports of scrapie in sheep and goats.

瘙痒病是一种自然发生的传染性海绵状脑病（TSE），会影响绵羊和山羊。绵羊和山羊可能会像羊羔或孩子一样感染瘙痒病通过接触胎盘或胎盘液体，或摄入环境中散发出的病毒和/或体液（例如唾液，尿液和粪便）。像其他TSE一样，通常在广泛且不可逆转的脑损伤发生之前就不会诊断瘙痒病。因此，一种可靠的动物筛查方法可能有助于诊断。另外，尽管已经广泛描述了绵羊中的天然瘙痒病，但是天然获得的山羊瘙痒病的特征较少。本研究的目的是就疾病表型（即潜伏期，临床体征，PrP ^Sc的神经解剖沉积模式）更好地了解天然山羊瘙痒病。，以及通过Western印迹检测到的分子图谱），并评估前验测试在山羊群中检测瘙痒病阳性动物的功效。简要地说，由于先前在该场所诊断出瘙痒病，因此从人口减少的农场中移出了28只暴露于瘙痒病的山羊，并每天进行观察30个月。在观察期间，对直肠肛门粘膜相关淋巴样组织（RAMALT）进行死前活检，并使用免疫组织化学和实时地震诱导的转化（RT-QuIC）进行测试，并测量视网膜厚度体内使用光学相干断层扫描（OCT）。在观察期之后，进行免疫组织化学和蛋白质印迹以评估PrP ^Sc的神经解剖沉积模式和分子谱。我们的结果表明，前肛门直肠穿刺活检可有效鉴定自然感染瘙痒病的山羊，而前肛门直肠穿刺活检阳性与神经系统疾病的临床体征和阳性大坝状态相关。我们报告说，在观察期内，天然感染瘙痒病的山羊无法检测到视网膜厚度的变化。最后，我们的结果表明PrP ^Sc的积累 在中枢神经系统（CNS）和非CNS组织中的表达与先前报道的绵羊和山羊瘙痒病的报道一致。