By Dr. Tony Frazier
I haven’t written many articles about sheep and goat diseases. But, according to the 2018 agriculture census, the state of Alabama had almost 50,000 goats. The report did not list the number of sheep or sheep farms, but the number of sheep and goats is continually increasing along with the number of farms. If you are not a goat or sheep producer, I would probably still read the article. You never know when you may be having a conversation with someone in that industry and you can impress them with your knowledge of scrapie and regulations.
Scrapie was first recognized about 250 years ago in Great Britain. It is a degenerative disease of sheep and goats that is 100% fatal. It is caused by prions, like the agent causing bovine spongiform encephalopathy, chronic wasting disease in deer and other diseases specific to certain species. However, scrapie took on some added significance back in the mid-1990s with the rise in cases of BSE in the United Kingdom. There was speculation, although it was never proven that cattle exposure to the scrapie prions may have been how BSE originated.
Scrapie identification by veterinarians on the farm is based on clinical signs and history. The disease is mostly classified as neurological. It may begin with tremors of the head and neck and pruritis, which means itching. Sheep will often rub their wool off as they scratch the itch caused by the disease. Weight loss and an altered gait that may resemble a rabbit hopping are also signs associated with scrapie. Transmission of the classical scrapie agent is not completely understood, and apparently healthy sheep infected with the agent can transmit disease. Sheep and goats are typically infected as young lambs or kids, though adult sheep and goats can become infected.
As many of you may remember, the BSE outbreak in Europe back in the 1990s resulted in many changes in the beef industry such as the removal of specified risk material (brains and spinal cords) of cattle over 2 years old. The specified risk material could no longer make it into the human food chain and could no longer be rendered for pet food or anything else, but had to be destroyed. Along with the changes affecting the cattle industry, a scrapie eradication program was implemented for sheep and goats.
Classical scrapie had, for the most part, only affected dark-faced sheep. However, atypical scrapie could affect nondark-faced sheep and goats, although at an extremely low frequency. Yet, in an abundance of caution, all sheep and goats were included in the requirements of the surveillance program. As the program rolled out, Dr. Cindy Brasfield, the USDA Veterinary Medical Officer who oversaw the program in our state at that time, and I sat down and put together the details of how the program could best be implemented in Alabama so the objectives could be achieved.
One of the main objectives of the program was to be able to trace any animal that became positive for scrapie back to the farm of origin. This was and continues to be achieved by using the official scrapie tag in the animal’s ear as it leaves the farm of origin. In Alabama, most sheep farms are participants in the program and have specific tags assigned to their farms. Yet, knowing the nature of the way things were done specific to Alabama, we allowed stockyards that were willing to do it to tag the animals as they entered the point of commerce and keep up with the information so we could still trace the tag numbers back to the farm of origin if needed.
The Scrapie Certified Flock Program has two categories, Select and Export. The Select component has an initial testing requirement. Unlike current testing for BSE, the live animal can be tested for scrapie. Without going into the details of the testing program, it provides the capability of finding the animals that may be incubating the disease as well as those most susceptible to and resistant to the disease.
The Export component has to do with record keeping and only adding animals to the flock that are of an equal status of surveillance or higher. It involves a higher level of surveillance, but opens the door for better marketing opportunities.
Recently, as we reviewed how our regulation was written several years ago, we did not allow for animals to travel off the farm to the point of commerce, which included processing plants, without first being tagged. The regulation pretty much requires the animals be tagged before leaving the farm. We are going to have to go back to the drawing board and amend our regulation. The plan is to allow sheep and goats to continue to move to stockyards and auctions or slaughter facilities without a scrapie tag. The reason for this exemption is that those facilities are already required by law to get the information allowing these animals to be traced to their farm of origin. The animals would then be officially tagged as needed. This may cause a little heartburn for the USDA folks in thinking about our compliance with the national scrapie program. I still believe the way we have done things has worked very well for producers in Alabama. That doesn’t mean that, when we amend our regulation and sit down with the USDA folks, they may not tell us we must go back and make sure the animals get tagged before leaving the farm of origin. If that happens, I will be back somewhere down the road letting you know how that worked out.
I have always tried to mold our regulations and requirements to fit how animals in our state are raised and marketed. Most of the time, USDA understands and agrees that if regulations become too burdensome or difficult for the producer the program will ultimately not be successful.
If you have questions or input into our scrapie surveillance or any other regulatory issue, don’t hesitate to get in touch with me. That is what they pay me for.