Submitted to: Conference Research Workers Disease Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/3/2006
Publication Date: 12/3/2006
Citation: Hamir, A.N., Kunkle, R.A., Cutlip, R.C., Miller, J.M., Williams, E.S., Richt, J.A. 2006. Transmission of chronic wasting disease of mule deer to Suffolk sheep following intracerebral inoculation [abstract]. Conference of Research Workers in Animal Diseases 87th Annual Meeting. Paper No. P34. p. 108.
Technical Abstract: To determine the transmissibility of chronic wasting disease (CWD) to sheep, 8 Suffolk lambs of various prion protein (PRNP) genotype (4 ARQ/ARR, 3 ARQ/ARQ, 1 ARQ/VRQ at codons 136, 154 and 171, respectively) were inoculated intracerebrally with brain suspension from mule deer with CWD (CWD**md). Two other lambs were kept as non inoculated controls. Within 36 months post inoculation (MPI), 2 inoculated animals became sick and were euthanized. Only 1 sheep (euthanized at 35 MPI) showed clinical signs that were consistent with those described for scrapie. Microscopic lesions of spongiform encephalopathy (SE) were only seen in this sheep and its tissues were positive for the abnormal prion protein (PrP**res) by immunohistochemistry and Western blot. Three other inoculated sheep were euthanized (36 to 60 MPI) because of conditions unrelated to TSE. The 3 remaining inoculated sheep and the 2 control sheep were non clinical at the termination of the study (72 MPI) and were euthanized. One of the 3 remaining inoculated sheep revealed SE and its tissues were positive for PrP**res. The sheep with clinical prion disease (euthanized at 35 MPI) was of the heterozygous genotype (ARQ/VRQ) and the sheep with the sub clinical disease (euthanized at 72 MPI) was of the homozygous ARQ/ARQ genotype. These findings demonstrate that transmission of the CWD**md agent to sheep via the intracerebral route is possible. Interestingly, the host genotype may play a significant part in successful transmission and incubation period of CWD**md.