NR AXON
AU Hoffmann,C.; Keller,M.; Seidowski,D.; Eiden,M.; Ziegler,U.; Kaatz,M.; Rogers,R.; Hills,B.; Buschmann,A.; Groschup,M.H.
TI Studies on the Infectivity Distribution of BSE in the Gut of Pre-clinical Cattle for Definition of Specified Risk Material
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Epidemiology, Risk Assessment and Transmission P04.64
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB To establish public health protection measures it is important to precisely define the tissues which must be considered as specified risk material (SRM). Intestine from duodenum to rectum is currently considered as SRM in the European Union - a definition which is largely based on the infectivity distribution in TSE infected sheep. In contrast only the distal Ileum will be removed as SRM in Canada. In clinically affected cattle (in experimental as well as natural conditions) no infectivity has yet been found outside of the Peyers patches of the distal ileum, neither by conventional mouse bioassay nor by IHC/WB. It must be acknowledged, however, that the sensitivity of these techniques is quite limited and no data are available for those tissues from cattle in the early BSE incubating time. We are therefore studying by when PrPsc and infectivity (if at all) can be found in the small intestine (particularly in the gut associated lymphoid tissue) of cattle which were challenged at the age of 4-6 month. For this purpose samples of the jejunum, the ileum and the ileocaecal junction from 22 orally dosed BSE (100g brain stem per animal) infected cattle which were culled after 4, 8, 12, 16, 20 and 24 months respectively, are examined by Immunohistochemistry, PTA Western Blot, IDEXX HerdChek ELISA, BioRad TeSeE and by Tgbov XV bioassay. The systematic approach of this study will allow mapping of the exact temporal and spatial emergence/distribution of PrPsc in the small intestine of cattle in particular in the gut associated lymphoid tissues. Such estimates have a critical role in qualitative and quantitative risk assessments and in providing advice on the designation and removal of certain SRM tissues according to age of cattle at slaughter. This study is funded by Health Canada.
AD C. Hoffmann, M. Keller, D. Seidowski, M. Eiden, U. Ziegler, M. Kaatz, A. Buschmann, M.H. Groschup, Friedrich-Löffler-Institut, Germany; R. Rogers, Health Canada, Bureau of Microbial Hazards, Heath Prod. & Food, Germany; B. Hills, Health Canada, Transmissible Spongiform Encephalopathy Secretaria, Germany
SP englisch
PO Schottland
EA pdf-Datei und Poster (Posterautoren ergänzt um B. Hammerschmidt)