Scrapie is a fatal, degenerative disease of the central nervous systems of sheep and goats. It belongs to the family of transmissible spongiform encephalopathies (TSEs), which includes Bovine Spongiform Encephalopathy (BSE or "mad cow disease"), Chronic Wasting Disease in deer, and Creutzfeldt-Jakob Disease in humans.
The infectious agent of the TSEs is now widely accepted to be an abnormal form of a protein called a prion. Normal prions are present in every mammal and bird. When an abnormal prion enters a healthy animal, it alters existing prions and changes them into the disease-associated form.
This disease is transferable among animals in the same herd. Cleanliness is important in preventing any potential transmission. Kids born into a contaminated environment are particularly susceptible as the disease can be transmitted through urine, feces, and contact with placental tissue. For this reason, using the "snatch and rear" method for raising kids is recommended in order to reduce potential transmission. Since there is no cure, it is important to quarantine and euthanize infected animals. Other animals in the herd can become infected by coming in contact with infected material in the birthing environment.
There does not appear to be any evidence to suggest that this disease is contagious to humans.
This disease progresses slowly. Young animals will not show signs of infection, yet they will still be contagious to other animals in the herd. Symptoms usually begin in animals around 2-5 years old. Symptoms may vary greatly from one goat to the next. Some may show signs of aggression, while others may show signs of apprehension. Some other signs can be lip smacking, convulsions, altered gait, a poor coat. Symptoms generally begin mildly, but will increase in severity as the disease progresses. After the onset of symptoms, the goat will die within a few months.
A post mortem examination is important for diagnosis. As of yet, there is no vaccine for prevention of the disease.
Goats with certain genetic types are less likely to become infected. Blood tests can determine the genetic profile of a goat. Producers that want to minimize the risk of contracting this disease in their herd can consider selective breeding for genetic resistance. However, it should be remembered that even genetically resistant goats are not completely immune. Ontario Goat has posted a helpful and informative article, entitled "Genetic Testing for Scrapie Resistance and Susceptibility" (by Mubrouka Elharram).
Keep a Closed Herd
Do not introduce new females to the herd as you could unknowingly cause an outbreak. If you plan on adding to your herd in this way, consider doing so with the greatest caution, so as to avoid infecting the entire herd.
Conduct Post Mortem Examinations
Any animal over 12 months of age that dies on your farm should be tested for presence of the disease.
In the absence of adopting specific measures to minimize the risk of contraction of the disease on their farm, a producer is encouraged to implement general good management and biosecurity practices, such as individual animal identification, record keeping, prompt isolation of sick animals, separation of females giving birth, increased cleanliness of the birthing environment, disinfection of equipment between animals, and single use needles for injections.