Article Text

Download PDFPDF
Pathogenesis of experimental bovine spongiform encephalopathy: preclinical infectivity in tonsil and observations on the distribution of lingual tonsil in slaughtered cattle
  1. G. A. H. Wells, BVetMed, FRCPath, DipECVP, DipACVP, MRCVS1,
  2. J. Spiropoulos, DVM, PhD, MRCVS1,
  3. S. A. C. Hawkins, MIBiol1 and
  4. S. J. Ryder, MA, VetMB, CertVR, PhD, MRCVS1
  1. 1Veterinary Laboratories Agency – Weybridge, New Haw, Addlestone, Surrey KT15 3NB


The infectivity in tissues from cattle exposed orally to the agent of BSE was assayed by the intracerebral inoculation of cattle. In addition to the infectivity in the central nervous system and distal ileum at stages of pathogenesis previously indicated by mouse bioassay, traces of infectivity were found in the palatine tonsil of cattle killed 10 months after exposure. Because the infectivity may therefore be present throughout the tonsils in cattle infected with BSE, observations were made of the anatomical and histological distribution of lingual tonsil in the root of the tongue of cattle. Examinations of tongues derived from abattoirs in Britain and intended for human consumption showed that macroscopically identifiable tonsillar tissue was present in more than 75 per cent of them, and even in the tongues in which no visible tonsillar tissue remained, histological examination revealed lymphoid tissue in more than 90 per cent. Variations in the distribution of the lingual tonsil suggested that even after the most rigorous trimming of the root of the tongue, traces of tonsillar tissue may remain.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.