title: BSE infectivity in jejunum, ileum and ileocaecal junction of incubating cattle.
abstract: To establish bovine spongiform encephalopathy (BSE) public health protection measures it is important to precisely define the cattle tissues considered as specified risk materials (SRM). To date, in pre-clinical BSE infected cattle, no evidence of the BSE agent had been found in the gut outside of the ileal Peyer's Patches. This study was undertaken to determine when and where the pathological prion protein (PrPSc) and/or BSE infectivity can be found in the small intestine of cattle 4 to 6 months of age, orally challenged with BSE. Samples of the jejunum, the ileum and the ileocaecal junction from 46 BSE infected cattle, culled from 1 up to 44 months post infection (mpi) were examined by immunohistochemistry. Samples from cattle 8 mpi to 20 mpi were additionally studied by PTA Western blot, rapid tests, and by mouse (TgbovXV) bioassay. In doing so nearly all of the cattle, from 4 up to 44 mpi, had detectable amounts of PrPSc and/or infectivity in the distal ileum. In the distal ileum clear time-dependent variations were visible concerning the amount of PrPSc, the tissue structures affected, and the cells involved. BSE infectivity was found not only in the ileum and ileocaecal junction but also in the jejunum. The systematic approach of this study provides new data for qualitative and quantitative risk assessments and allows defining bovine SRM more precisely.
authors.affiliation: Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Südufer 10, 17493 Greifswald-Insel Riems, Germany. martin.groschup@fli.bund.de.
authors.forename: Christine
authors.initials: C
authors.lastname: Hoffmann
authors.forename: Martin
authors.initials: M
authors.lastname: Eiden
authors.forename: Martin
authors.initials: M
authors.lastname: Kaatz
authors.forename: Markus
authors.initials: M
authors.lastname: Keller
authors.forename: Ute
authors.initials: U
authors.lastname: Ziegler
authors.forename: Ron
authors.initials: R
authors.lastname: Rogers
authors.forename: Bob
authors.initials: B
authors.lastname: Hills
authors.forename: Anne
authors.initials: A
authors.lastname: Balkema-Buschmann
authors.forename: Lucien
authors.initials: L
authors.lastname: van Keulen
authors.forename: Jorg G
authors.initials: JG
authors.lastname: Jacobs
authors.forename: Martin H
authors.initials: MH
authors.lastname: Groschup
mesh_terms: D000375:Aging; D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D002417:Cattle; D016643:Encephalopathy, Bovine Spongiform / Q000473:pathology* / Q000635:transmission; D005260:Female; D007082:Ileum / Q000473:pathology*; D007583:Jejunum / Q000473:pathology*; D051379:Mice; D008822:Mice, Transgenic; D018620:PrPSc Proteins / Q000032:analysis*; D018570:Risk Assessment
chemical_list: D018620:PrPSc Proteins