Research Seeks to Prevent Scrapie
Reprinted from "Hobby Farms Magazine"
If you have goats or sheep on your farm, one word you never want to hear from your vet is "scrapie," a form of transmissible spongiform encephalopathy--basically a degenerative disease of the brain. Scrapie causes tremors, lip-smacking, weight loss, a hopping gait, and other odd symptoms. The disease is incurable, and animals eventually die...until possibly now.
Scientists at the USDA Agricultural Research Service developed a live-animal test to detect scrapie in sheep and goats. This method, called the rectal mucosa biopsy test or rectal biopsy, requires snipping a tiny piece of lymphoid tissue from the lining of the afflicted animal's rectum. Microbiologist Katherine O'Rourke, a member of the scrapie research team, says the lymphoid tissue is tested because it collects malformed proteins called prions, which are thought to cause scrapie.
Scientists are also working to prevent scrapie with selective breeding and increase numbers of sheep with the prion protein gene dubbed R171 that resists the disease. However, goats have not yet been found to have R171.
"In sheep, the discovery of resistance genes was key to developing a broadly accepted eradication program. If scrapie is found in a flock, only the genetically susceptible sheep are removed, allowing the producer to maintain quality animals," says O'Rourke. "As we learn more about goat genetic resistance, we hope the same approach can work for them."
According to the USDA, ARS Pullman geneticist Stephen White is leading studies to characterize the prion protein gene of goats and identify differences between individual animals and breeds harboring the gene. So far, the team has examined alleles from 446 goats, including the Alpine, Angora, Boer, and Nubian breeds.
To date only one incidence of scrapie in Babydolls has been found, all on one farm. This was several years ago, and as I remember, it was about six sheep. The government reimbursed the owner for the sheep. All sheep now are supposed to be in the National Scrapie Program. Many of our breeders are. Your State Department of Agriculture provides the ear tags and the tool to attach the tags for free. The tags have the initials of the state, your farm identification number, and the last digits of the individual's number. I believe that it is a requirement for the export of sheep to Canada. If you are not using the scrapie tags, I urge you to do so this year.---Robert Mock.