Preliminary Observations on the Experimental Transmission of Chronic Wasting Disease (CWD) from Elk and White-Tailed Deer to Fallow Deer

• Published in: Journal of comparative pathology Vol. 138; no. 2; pp. 121 - 130
• Main Authors: Hamir, A.N., Kunkle, R.A., Nicholson, E.M., Miller, J.M., Hall, S.M., Schoenenbruecher, H., Brunelle, B.W., Richt, J.A.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.02.2008
• Subjects: Animals; Blotting, Western; Brain - metabolism; Brain - pathology; Cervus dama; chronic wasting disease; Deer; diagnostic techniques; disease detection; Disease Susceptibility; disease transmission; Disease Transmission, Infectious; DNA, Viral - analysis; elks; fallow deer; fawns; Female; histopathology; Immunohistochemistry; infection; intracerebral inoculation; lesions (animal); Male; Odocoileus virginianus; Polymerase Chain Reaction; prion; prions; Prions - genetics; Prions - metabolism; Prions - pathogenicity; Serial Passage; signs and symptoms (animals and humans); Spinal Cord - metabolism; Spinal Cord - pathology; spongiform encephalopathy; Wasting Disease, Chronic - metabolism; Wasting Disease, Chronic - pathology; Wasting Disease, Chronic - transmission; chronic wasting disease; prion; fallow deer; spongiform encephalopathy
• ISSN: 0021-9975; 1532-3129
• DOI: 10.1016/j.jcpa.2007.12.002

To determine the transmissibility of chronic wasting disease (CWD) to fallow deer ( Dama dama) and to provide information about clinical course, lesions and suitability of currently used diagnostic procedures for detection of CWD in this species, 13 fawns were inoculated intracerebrally with CWD brain suspension from elk ( n = 6) or white-tailed deer ( n = 7). Three other fawns were kept as uninfected controls. Three CWD-inoculated deer were killed 7.6 months post-inoculation (mpi). None had abnormal prion protein (PrP d) in their tissues. One sick deer died at 24 mpi and one deer without clinical signs was killed at 26 mpi. Both animals had a small focal accumulation of PrP d in the midbrain. Between 29 and 37 mpi, three other deer became sick and were killed. All had shown gradual decrease in appetite and some loss of body weight. Microscopical lesions of spongiform encephalopathy were not observed, but PrP d was detected in tissues of the central nervous system (CNS) by immunohistochemistry, western blot and by two commercially available rapid diagnostic tests. This study demonstrates that intracerebrally inoculated fallow deer amplified CWD PrP d from white-tailed deer and elk in the absence of lesions of spongiform encephalopathy. Four years after CWD inoculation, the remaining five inoculated and two control deer are alive and apparently healthy.