1887

Abstract

Several studies have shown that transmission of natural scrapie can occur vertically and horizontally, and that variations in scrapie incidence between and within infected flocks are mostly due to differences in the proportion of sheep with susceptible and resistant genotypes. This report presents the results of a 12-year period of scrapie monitoring in a closed flock of Suffolk sheep, in which only animals of the ARQ/ARQ genotype developed disease. Among a total of 120 of these, scrapie attack rates varied between birth cohorts from 62.5 % (5/8) to 100 % (9/9), and the incidence of clinical disease among infected sheep from 88.9 % (8/9) to 100 % (in five birth cohorts). Susceptible sheep born to scrapie-infected ewes showed a slightly higher risk of becoming infected (97.2 %), produced earlier biopsy-positive results (mean 354 days) and developed disease at a younger age (median 736 days) than those born to non-infected dams (80.3 %, 451 and 782 days, respectively). Taken together, this was interpreted as evidence of maternal transmission. However, it was also observed that, for the birth cohorts with the highest incidence of scrapie (90–100 %), sheep born to infected and non-infected dams had a similar risk of developing scrapie (97.1 and 95.3 %, respectively). Compared with moderate-attack-rate cohorts (62.5–66.7 %), high-incidence cohorts had greater numbers of susceptible lambs born to infected ewes, suggesting that increased rates of horizontal transmission in these cohorts could have been due to high levels of environmental contamination caused by infected placentas.

Loading

Article metrics loading...

/content/journal/jgv/10.1099/vir.0.034652-0
2012-01-01
2024-12-13
Loading full text...

Full text loading...

/deliver/fulltext/jgv/93/1/203.html?itemId=/content/journal/jgv/10.1099/vir.0.034652-0&mimeType=html&fmt=ahah

References

  1. Andréoletti O., Lacroux C., Chabert A., Monnereau L., Tabouret G., Lantier F., Berthon P., Eychenne F., Lafond-Benestad S. other authors 2002; PrPSc accumulation in placentas of ewes exposed to natural scrapie: influence of foetal PrP genotype and effect on ewe-to-lamb transmission. J Gen Virol 83:2607–2616[PubMed]
    [Google Scholar]
  2. Baylis M., Goldmann W., Houston F., Cairns D., Chong A., Ross A., Smith A., Hunter N., McLean A. R. 2002; Scrapie epidemic in a fully PrP-genotyped sheep flock. J Gen Virol 83:2907–2914[PubMed]
    [Google Scholar]
  3. Begara-McGorum I., González L., Simmons M., Hunter N., Houston F., Jeffrey M. 2002; Vacuolar lesion profile in sheep scrapie: factors influencing its variation and relationship to disease-specific PrP accumulation. J Comp Pathol 127:59–68 [View Article][PubMed]
    [Google Scholar]
  4. Belt P. B. G. M., Muileman I. H., Schreuder B. E. C., Bos-de Ruijter J., Gielkens A. L. J., Smits M. A. 1995; Identification of five allelic variants of the sheep PrP gene and their association with natural scrapie. J Gen Virol 76:509–517 [View Article][PubMed]
    [Google Scholar]
  5. Clouscard C., Beaudry P., Elsen J. M., Milan D., Dussaucy M., Bounneau C., Schelcher F., Chatelain J., Launay J. M., Laplanche J. L. 1995; Different allelic effects of the codons 136 and 171 of the prion protein gene in sheep with natural scrapie. J Gen Virol 76:2097–2101 [View Article][PubMed]
    [Google Scholar]
  6. Dawson M., Moore R. C., Bishop S. C. 2008; Progress and limits of PrP gene selection policy. Vet Res 39:25 [View Article][PubMed]
    [Google Scholar]
  7. Detwiler L. A., Baylis M. 2003; The epidemiology of scrapie. Rev Sci Tech 22:121–143[PubMed]
    [Google Scholar]
  8. Dickinson A. G., Stamp J. T., Renwick C. C. 1974; Maternal and lateral transmission of scrapie in sheep. J Comp Pathol 84:19–25 [View Article][PubMed]
    [Google Scholar]
  9. Elsen J.-M., Amigues Y., Schelcher F., Ducrocq V., Andreoletti O., Eychenne F., Tien Khang J. V., Poivey J.-P., Lantier F., Laplanche J.-L. 1999; Genetic susceptibility and transmission factors in scrapie: detailed analysis of an epidemic in a closed flock of Romanov sheep. Arch Virol 144:431–445 [View Article][PubMed]
    [Google Scholar]
  10. Espenes A., Press C. McL., Landsverk T., Tranulis M. A., Aleksandersen M., Gunnes G., Benestad S. L., Fuglestveit R., Ulvund M. J. 2006; Detection of PrPSc in rectal biopsy and necropsy samples from sheep with experimental scrapie. J Comp Pathol 134:115–125 [View Article][PubMed]
    [Google Scholar]
  11. Foster J., McKenzie C., Parnham D., Drummond D., Goldmann W., Stevenson E., Hunter N. 2006; Derivation of a scrapie-free sheep flock from the progeny of a flock affected by scrapie. Vet Rec 159:42–45 [View Article][PubMed]
    [Google Scholar]
  12. Garza M. C., Fernández-Borges N., Acín C., Badiola J. J., Castilla J., Monleón E. 2011; Detection of PrPSc in fetal tissues from natural scrapie infected ewes [poster presentation]. Prion 5:Suppl.22[PubMed] [CrossRef]
    [Google Scholar]
  13. Goldmann W., Houston F., Stewart P., Perucchini M., Foster J., Hunter N. 2006; Ovine prion protein variant A136R154L168Q171 increases resistance to experimental challenge with bovine spongiform encephalopathy agent. J Gen Virol 87:3741–3745 [View Article][PubMed]
    [Google Scholar]
  14. González L., Martin S., Begara-McGorum I., Hunter N., Houston F., Simmons M., Jeffrey M. 2002; Effects of agent strain and host genotype on PrP accumulation in the brain of sheep naturally and experimentally affected with scrapie. J Comp Pathol 126:17–29 [View Article][PubMed]
    [Google Scholar]
  15. González L., Dagleish M. P., Bellworthy S. J., Sisó S., Stack M. J., Chaplin M. J., Davis L. A., Hawkins S. A. C., Hughes J., Jeffrey M. 2006; Postmortem diagnosis of preclinical and clinical scrapie in sheep by the detection of disease-associated PrP in their rectal mucosa. Vet Rec 158:325–331 [View Article][PubMed]
    [Google Scholar]
  16. González L., Dagleish M. P., Martin S., Dexter G., Steele P., Finlayson J., Jeffrey M. 2008; Diagnosis of preclinical scrapie in live sheep by the immunohistochemical examination of rectal biopsies. Vet Rec 162:397–403 [View Article][PubMed]
    [Google Scholar]
  17. Hamilton S., Finlayson J., Pang Y., Buxton D., Eaton S., Steele P., Dagleish M., Benavides J., González L. other authors 2008; PrPsc distribution in perfused placentas from Suffolk sheep naturally infected with scrapie. In: Proceedings of Prion 2008 Conference, 8–10 October 2008, Madrid, Spain, p. 82
    [Google Scholar]
  18. Healy A. M., Hannon D., Morgan K. L., Weavers E., Collins J. D., Doherty M. L. 2004; A paired case–control study of risk factors for scrapie in Irish sheep flocks. Prev Vet Med 64:73–83 [View Article][PubMed]
    [Google Scholar]
  19. Hoinville L. J. 1996; A review of the epidemiology of scrapie in sheep. Rev Sci Tech 15:827–852[PubMed]
    [Google Scholar]
  20. Hoinville L. J., Tongue S. C., Wilesmith J. W. 2010; Evidence for maternal transmission of scrapie in naturally affected flocks. Prev Vet Med 93:121–128 [View Article][PubMed]
    [Google Scholar]
  21. Hosie B. D., Dingwall W. S., Moore L., Hunter N. 1997; A recent outbreak of scrapie in the ESCA Suffolk flock. Proc Sheep Veterinary Society 21:53–56
    [Google Scholar]
  22. Hourrigan J., Klingsporn A., Clark W. W., DeCamp M. 1979; Epidemiology of scrapie in the United States. In Slow Transmissible Diseases of the Nervous System pp. 331–356 Edited by Prusiner S. B., Hadlow W. B. New York: Academic Press;
    [Google Scholar]
  23. Hunter N., Goldmann W., Smith G., Hope J. 1994; The association of a codon 136 PrP gene variant with the occurrence of natural scrapie. Arch Virol 137:171–177 [View Article][PubMed]
    [Google Scholar]
  24. Hunter N., Moore L., Hosie B. D., Dingwall W. S., Greig A. 1997; Association between natural scrapie and PrP genotype in a flock of Suffolk sheep in Scotland. Vet Rec 140:59–63 [View Article][PubMed]
    [Google Scholar]
  25. Ikeda T., Horiuchi M., Ishiguro N., Muramatsu Y., Kai-Uwe G. D., Shinagawa M. 1995; Amino acid polymorphisms of PrP with reference to onset of scrapie in Suffolk and Corriedale sheep in Japan. J Gen Virol 76:2577–2581 [View Article][PubMed]
    [Google Scholar]
  26. Jeffrey M., Martin S., Thomson J. R., Dingwall W. S., Begara-McGorum I., González L. 2001; Onset and distribution of tissue PrP accumulation in scrapie-affected Suffolk sheep as demonstrated by sequential necropsies and tonsillar biopsies. J Comp Pathol 125:48–57 [View Article][PubMed]
    [Google Scholar]
  27. Konold T., Moore S. J., Bellworthy S. J., Simmons H. A. 2008; Evidence of scrapie transmission via milk. BMC Vet Res 4:14 [View Article][PubMed]
    [Google Scholar]
  28. Lacroux C., Corbière F., Tabouret G., Lugan S., Costes P., Mathey J., Delmas J. M., Weisbecker J. L., Foucras G. other authors 2007; Dynamics and genetics of PrPSc placental accumulation in sheep. J Gen Virol 88:1056–1061 [View Article][PubMed]
    [Google Scholar]
  29. Lacroux C., Simon S., Benestad S. L., Maillet S., Mathey J., Lugan S., Corbière F., Cassard H., Costes P. other authors 2008; Prions in milk from ewes incubating natural scrapie. PLoS Pathog 4:e1000238 [View Article][PubMed]
    [Google Scholar]
  30. Laegreid W. W., Clawson M. L., Heaton M. P., Green B. T., O’Rourke K. I., Knowles D. P. 2008; Scrapie resistance in ARQ sheep. J Virol 82:10318–10320 [View Article][PubMed]
    [Google Scholar]
  31. Low J. C., Chambers J., McKelvey W. A. C., McKendrick I. J., Jeffrey M. 2009; Failure to transmit scrapie infection by transferring preimplantation embryos from naturally infected donor sheep. Theriogenology 72:809–816 [View Article][PubMed]
    [Google Scholar]
  32. Maddison B. C., Rees H. C., Baker C. A., Taema M., Bellworthy S. J., Thorne L., Terry L. A., Gough K. C. 2010; Prions are secreted into the oral cavity in sheep with preclinical scrapie. J Infect Dis 201:1672–1676 [View Article][PubMed]
    [Google Scholar]
  33. Redman C. A., Coen P. G., Matthews L., Lewis R. M., Dingwall W. S., Foster J. D., Chase-Topping M. E., Hunter N., Woolhouse M. E. J. 2002; Comparative epidemiology of scrapie outbreaks in individual sheep flocks. Epidemiol Infect 128:513–521 [View Article][PubMed]
    [Google Scholar]
  34. Saunders G. C., Lantier I., Cawthraw S., Berthon P., Moore S. J., Arnold M. E., Windl O., Simmons M. M., Andréoletti O. other authors 2009; Protective effect of the T112 PrP variant in sheep challenged with bovine spongiform encephalopathy. J Gen Virol 90:2569–2574 [View Article][PubMed]
    [Google Scholar]
  35. Sisó S., Jeffrey M., Steele P., McGovern G., Martin S., Finlayson J., Chianini F., González L. 2008; Occurrence and cellular localization of PrPd in kidneys of scrapie-affected sheep in the absence of inflammation. J Pathol 215:126–134 [View Article][PubMed]
    [Google Scholar]
  36. Sisó S., Jeffrey M., González L. 2009; Neuroinvasion in sheep transmissible spongiform encephalopathies: the role of the haematogenous route. Neuropathol Appl Neurobiol 35:232–246 [View Article][PubMed]
    [Google Scholar]
  37. Sisó S., Jeffrey M., Martin S., Chianini F., Dagleish M. P., González L. 2010; Characterization of strains of ovine transmissible spongiform encephalopathy with a short PrPd profiling method. J Comp Pathol 142:300–310 [View Article][PubMed]
    [Google Scholar]
  38. Touzeau S., Chase-Topping M. E., Matthews L., Lajous D., Eychenne F., Hunter N., Foster J. D., Simm G., Elsen J. M., Woolhouse M. E. J. 2006; Modelling the spread of scrapie in a sheep flock: evidence for increased transmission during lambing seasons. Arch Virol 151:735–751 [View Article][PubMed]
    [Google Scholar]
  39. Tuo W., Zhuang D., Knowles D. P., Cheevers W. P., Sy M. S., O’Rourke K. I. 2001; Prp-C and Prp-Sc at the fetal–maternal interface. J Biol Chem 276:18229–18234 [View Article][PubMed]
    [Google Scholar]
  40. Vaccari G., Scavia G., Sala M., Cosseddu G., Chiappini B., Conte M., Esposito E., Lorenzetti R., Perfetti G. other authors 2009; Protective effect of the AT137RQ and ARQK176 PrP allele against classical scrapie in Sarda breed sheep. Vet Res 40:19 [View Article][PubMed]
    [Google Scholar]
  41. Wang S., Foote W. C., Sutton D. L., Maciulis A., Miller J. M., Evans R. C., Holyoak G. R., Call J. W., Bunch T. D. other authors 2001; Preventing experimental vertical transmission of scrapie by embryo transfer. Theriogenology 56:315–327 [View Article][PubMed]
    [Google Scholar]
  42. Westaway D., Zuliani V., Cooper C. M., Da Costa M., Neuman S., Jenny A. L., Detwiler L., Prusiner S. B. 1994; Homozygosity for prion protein alleles encoding glutamine-171 renders sheep susceptible to natural scrapie. Genes Dev 8:959–969 [View Article][PubMed]
    [Google Scholar]
/content/journal/jgv/10.1099/vir.0.034652-0
Loading
/content/journal/jgv/10.1099/vir.0.034652-0
Loading

Data & Media loading...

Supplements

Supplementary material 1

PDF
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