Intracerebral transmission of scrapie to cattle.
To determine if sheep scrapie agent(s) in the United States would induce a disease in cattle resembling bovine spongiform encephalopathy, 18 newborn calves were inoculated intracerebrally with a pooled suspension of brain from 9 sheep with scrapie. Half of the calves were euthanatized 1 year after inoculation. All calves kept longer than 1 year became severely lethargic and demonstrated clinical signs of motor neuron dysfunction that were manifest as progressive stiffness, posterior paresis, general weakness, and permanent recumbency. The incubation period was 14-18 months, and the clinical course was 1-5 months. The brain from each calf was examined for lesions and for protease-resistant prion protein. Lesions were subtle, but a disease-specific isoform of the prion protein was present in the brain of all calves. Neither signs nor lesions were characteristic of those for bovine spongiform encephalopathy.
Cutlip
R C
RC
USDA, Agriculture Research Service, National Animal Disease Center, Ames, IA 50010.
Miller
J M
JM
Race
R E
RE
Jenny
A L
AL
Katz
J B
JB
Lehmkuhl
H D
HD
DeBey
B M
BM
Robinson
M M
MM
D000818:Animals; D001921:Brain / Q000382:microbiology* / Q000473:pathology; D002417:Cattle; D002418:Cattle Diseases / Q000209:etiology* / Q000473:pathology; D016643:Encephalopathy, Bovine Spongiform / Q000209:etiology* / Q000473:pathology; D015151:Immunoblotting / Q000662:veterinary; D007150:Immunohistochemistry; D008297:Male; D009046:Motor Neurons / Q000502:physiology; D011328:Prions / Q000032:analysis; D012608:Scrapie / Q000473:pathology / Q000635:transmission*; D012756:Sheep; D012894:Sleep Stages; D013997:Time Factors
D011328:Prions