title: Atypical scrapie in a Swiss goat and implications for transmissible spongiform encephalopathy surveillance.
abstract: Different types of transmissible spongiform encephalopathies (TSEs) affect sheep and goats. In addition to the classical form of scrapie, both species are susceptible to experimental infections with the bovine spongiform encephalopathy (BSE) agent, and in recent years atypical scrapie cases have been reported in sheep from different European countries. Atypical scrapie in sheep is characterized by distinct histopathologic lesions and molecular characteristics of the abnormal scrapie prion protein (PrP(sc)). Characteristics of atypical scrapie have not yet been described in detail in goats. A goat presenting features of atypical scrapie was identified in Switzerland. Although there was no difference between the molecular characteristics of PrP(sc) in this animal and those of atypical scrapie in sheep, differences in the distribution of histopathologic lesions and PrP(sc) deposition were observed. In particular the cerebellar cortex, a major site of PrP(sc) deposition in atypical scrapie in sheep, was found to be virtually unaffected in this goat. In contrast, severe lesions and PrP(sc) deposition were detected in more rostral brain structures, such as thalamus and midbrain. Two TSE screening tests and PrP(sc) immunohistochemistry were either negative or barely positive when applied to cerebellum and obex tissues, the target samples for TSE surveillance in sheep and goats. These findings suggest that such cases may have been missed in the past and could be overlooked in the future if sampling and testing procedures are not adapted. The epidemiological and veterinary public health implications of these atypical cases, however, are not yet known.
authors: NeuroCenter, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, Bremgartenstrasse 109a, CH-3001 Berne, Switzerland. torsten.seuberlich@itn.unibe.ch
authors: Torsten
authors: T
authors: Seuberlich
authors: Catherine
authors: C
authors: Botteron
authors: Sylvie L
authors: SL
authors: Benestad
authors: Hervé
authors: H
authors: Brünisholz
authors: Reto
authors: R
authors: Wyss
authors: Ulrich
authors: U
authors: Kihm
authors: Heinzpeter
authors: H
authors: Schwermer
authors: Martina
authors: M
authors: Friess
authors: Alexandra
authors: A
authors: Nicolier
authors: Dagmar
authors: D
authors: Heim
authors: Andreas
authors: A
authors: Zurbriggen
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology; D015511:Goat Diseases / Q000175:diagnosis*; D006041:Goats; D007150:Immunohistochemistry; D008297:Male; D017096:Prion Diseases; D012608:Scrapie / Q000175:diagnosis*