Scrapie Disease

A fatal disease in sheep and goats.

Let's talk about scrapie disease for a moment.  What is it?  Scrapie is a fatal, degenerative disease that affects the nervous systems of sheep and goats.  It is one of several transmissible spongiform encephalopathies (TSEs), which are related to bovine spongiform encephalopathy (BSE or "mad cow disease") and chronic wasting disease of deer. Scrapie has been known since 1732 and does not appear to be transmissible to humans.  There is no treatment available. 


Through DNA testing, it is possible to tell if sheep have an inherited resistance to this disease.  Here at Lone Star Farm, all of our sheep are tested to see if they have this resistance.  Some do and some don't. There has never been a case of scrapie diagnosed in a Barbados Blackbelly sheep thus far.  Still, we check every sheep on our farm.  One of the reasons is the fact that some states are beginning to require that each sheep crossing their borders must be tested and show some resistance to the disease before they will be allowed entry.  This disease is transmissible from sheep to their deer population and they are very serious about protecting their wildlife.  There are several laboratories that do this testing, but we use GeneCheck, Inc. in Greeley, Colorado.  We collect our own samples through a tiny hole punched in the lamb's ear.  That piece of tissue is deposited in a collection tag that is then sent to the lab for testing.  Results are forthcoming within a week. 


There are several results that can be detected, but suffice it to say that ordinarily there are three significant results.  Namely QQ, QR and RR.  QQ means that the lamb does  not have resistance to the disease.  QR means that the lamb does have resistance to the disease.  RR means that not only does the lamb have resistance, but it will pass that resistance on to any lamb it produces.  By careful breeding, it is possible to produce an entire flock of RR sheep.  We once did a custom breeding for a gentleman whose state required that each sheep have at least one R in its test results.  Let me explain. Each parent has two alleles in their DNA makeup that relate to the resistance of the disease.  The lamb will inherit only one allele from each parent.  If you breed a QQ ewe to a QQ ram, it is only possible to get a QQ lamb.  If you breed an RR ewe to an RR ram, the only possible outcome is an RR lamb.  If however, you breed any other combination of Q and R, you can get any combination of Q and R in each lamb.  QQ bred to QR has one in four chances of inheriting resistance to the disease.  QR bred to QR obviously has a better chance of inheriting it.  QR bred to RR has an even better chance of not only inheriting the resistance, but a chance to be an RR with the ability to pass this resistance on to every lamb it gives birth to or sires. That being the case, you probably wonder why we would have any QQ sheep at Lone Star Farm, with all the testing we are doing.  It is because that characteristic is not the only thing to consider in breeding for the best Barbados Blackbelly possible.  The animal's temperament, conformation, prolificacy, parasite tolerance, breeding year round and mothering instincts are all desirable characteristics that must be taken into consideration each time one breeds. We consider all of these traits each time we breed.  Just know that all sheep on our farm have been tested and when you purchase a sheep from us, a certificate stating what their test results showed, will accompany their registration certificate along with a four generation pedigree.


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Lone Star Farm | Barbados Blackbelly Sheep