1887

Abstract

If BSE (bovine spongiform encephalopathy) infected the UK sheep population concurrently with cattle, it would only now be maintained by transmission between sheep by routes which could include from mother to lamb either or via perinatal close contact. In this study of experimental BSE, Cheviot ewes challenged orally with BSE cattle brain produced lambs of various PrP genotypes over the next 7 years. Of 72 surviving to >30 months of age, 29 are of the most susceptible PrP genotype (AQ/AQ) and born to mothers that were challenged with BSE. None of the progeny have shown any signs of disease. The results suggest that in these sheep, BSE could only transmit by the maternal route at a frequency of less than one in four (95 % confidence limit) from clinically affected ewes, a rate which if replicated in other breeds may not be sufficient to maintain BSE within the sheep population.

Loading

Article metrics loading...

/content/journal/jgv/10.1099/vir.0.80099-0
2004-10-01
2019-10-21
Loading full text...

Full text loading...

/deliver/fulltext/jgv/85/10/vir853159.html?itemId=/content/journal/jgv/10.1099/vir.0.80099-0&mimeType=html&fmt=ahah

References

  1. Andreoletti, O., Lacroux, C., Chabert, A. & 8 other authors ( 2002; ). PrPSc accumulation in placentas of ewes exposed to natural scrapie: influence of foetal genotype and effect on ewe-to-ewe lamb transmission. J Gen Virol 83, 2607–2616.
    [Google Scholar]
  2. Bruce, M. E., Chree, A., McConnell, I., Foster, J. D., Pearson, G. & Fraser, H. ( 1994; ). Transmission of bovine spongiform encephalopathy and scrapie to mice: strain variation and the species barrier. Philos Trans R Soc Lond B Biol Sci 343, 405–411.[CrossRef]
    [Google Scholar]
  3. Dickinson, A. G., Stamp, J. T. & Renwick, C. C. ( 1974; ). Maternal and lateral transmission of scrapie in sheep. J Comp Pathol 84, 19–25.[CrossRef]
    [Google Scholar]
  4. Foster, J. D., Bruce, M., McConnell, I., Chree, A. & Fraser, H. ( 1996; ). Detection of BSE infectivity in brain and spleen of experimentally infected sheep. Vet Rec 138, 546–548.[CrossRef]
    [Google Scholar]
  5. Foster, J. D., McKelvey, W., Fraser, H., Chong, A., Ross, A., Parnham, D., Goldmann, W. & Hunter, N. ( 1999; ). Experimentally induced bovine spongiform encephalopathy did not transmit via goat embryos. J Gen Virol 80, 517–524.
    [Google Scholar]
  6. Foster, J. D., Parnham, D. W., Hunter, N. & Bruce, M. ( 2001a; ). Distribution of the prion protein in sheep terminally affected with BSE following experimental oral transmission. J Gen Virol 82, 2319–2326.
    [Google Scholar]
  7. Foster, J. D., Parnham, D., Chong, A., Goldmann, W. & Hunter, N. ( 2001b; ). Clinical signs, histopathology and genetics of experimental transmission of BSE and natural scrapie to sheep and goats. Vet Rec 148, 165–171.[CrossRef]
    [Google Scholar]
  8. Goldmann, W., Hunter, N., Smith, G., Foster, J. & Hope, J. ( 1994; ). PrP genotype and agent effects in scrapie: change in allelic interaction with different isolates of agent in sheep, a natural host of scrapie. J Gen Virol 75, 989–995.[CrossRef]
    [Google Scholar]
  9. Gravenor, M. B., Ryder, S. J., Gubbins, S., Hunter, N., Baylis, M. & Kao, R. R. ( 2003; ). Searching for BSE in sheep: interpreting the results so far. Vet Rec 152, 298–299.[CrossRef]
    [Google Scholar]
  10. Houston, F., Goldmann, W., Chong, A., Jeffrey, M., Gonzalez, L., Foster, J., Parnham, D. & Hunter, N. ( 2003; ). Prion diseases: BSE in sheep bred for resistance to infection. Nature 423, 498.[CrossRef]
    [Google Scholar]
  11. Jeffrey, M., Ryder, S., Martin, S., Hawkins, S. A. C., Terry, L., Berthelin-Baker, C. & Bellworthy, S. J. ( 2001; ). Oral inoculation of sheep with the agent of bovine spongiform encephalopathy (BSE). 1. Onset and distribution of disease-specific PrP accumulation in brain and viscera. J Comp Pathol 124, 280–289.[CrossRef]
    [Google Scholar]
  12. Race, R., Jenny, A. & Sutton, D. ( 1998; ). Scrapie infectivity and proteinase K-resistant prion protein in sheep placenta, brain, spleen and lymph node: implications for transmission and antemortem diagnosis. J Infect Dis 178, 949–953.[CrossRef]
    [Google Scholar]
  13. Terry, L. A., Marsh, S., Ryder, S. J., Hawkins, S. A. C., Wells, G. A. H. & Spencer, Y. I. ( 2003; ). Detection of disease-specific PrP in the distal ileum of cattle exposed orally to the agent of bovine spongiform encephalopathy. Vet Rec 152, 387–392.[CrossRef]
    [Google Scholar]
  14. Wells, G. A. H. & Wilesmith, J. W. ( 1995; ). The neuropathology and epidemiology of bovine spongiform encephalopathy. Brain Pathol 5, 91–103.[CrossRef]
    [Google Scholar]
  15. Wells, G. A. H., Hawkins, S. A. C., Green, R. B., Austin, A. R., Dexter, I., Spencer, Y. I., Chaplin, M. J., Stack, M. J. & Dawson, M. ( 1998; ). Preliminary observations on the pathogenesis of experimental bovine spongiform encephalopathy (BSE): an update. Vet Rec 142, 103–106.[CrossRef]
    [Google Scholar]
  16. Wilesmith, J. W., Wells, G. A. H., Ryan, J. B. M., Gavier-Widen, D. & Simmons, M. M. ( 1997; ). A cohort study to examine maternally-associated risk factors for bovine spongiform encephalopathy. Vet Rec 141, 239–243.[CrossRef]
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jgv/10.1099/vir.0.80099-0
Loading
/content/journal/jgv/10.1099/vir.0.80099-0
Loading

Data & Media loading...

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error