Scrapie is a member of a family of diseases known as Transmissible Spongiform Encephalopathies (TSEs). Other TSEs include Bovine Spongiform Encephalopathy in cattle, Chronic Wasting Disease in deer and elk, and Creutzfeldt-Jakob disease in humans. TSEs are caused by an infectious protein called a prion. After prions are eaten, they travel through the body to the brain. Prions change normal proteins into more prions and cause “holes” to form in the brain, making it look like a sponge under a microscope.
The disease is called scrapie because infected sheep become very itchy and scrape off their wool while
rubbing against fences and barns. Sheep and goats are infected with scrapie at a very young age, but may not show symptoms of the disease until two to six years of age. Goats are susceptible to scrapie when raised with sheep, but goats do not appear to spread the disease. Scrapie symptoms develop slowly and may include weight loss, excessive itching/rubbing, wool pulling or biting, lip smacking, poor coordination, startling, high-stepping gait or bunny-hopping, tremors, inability to rise, and death.
Sheep and goat producers, working in collaboration with USDA and state agriculture agencies, have almost eliminated scrapie from the United States through testing, tagging, and selective breeding.
Scrapie tag manufacturers (USDA)
Genetics of Scrapie – Virginia Tech
Genetic Testing for Scrapie Resistance and Susceptibility – Ontario Goat
Scrapie – Nebraska Department of Agriculture