Thursday, August 2, 2012

Doberman Health: vonWillebrand's Disease

On Sunday night/Monday morning I had the unfortunate experience of having quicked Elka's nail while trimming it. Other than Wednesday, it's rather become this week's theme, unfortunately. That's my life, no shortage of inspiration, I guess!

Part of the reason I've been talking about what seems like such a minor thing all week is the fact that her nail bled for so long. It was unsettling, to say in the least. I didn't think that it was life threatening, as I knew that Elka was a carrier for vonWillebrand's disease, but neither affected nor clinically affected. And then I realized that it was time to talk about vWD.


von Willebrand's disease is, in short, a clotting disorder in dogs. VetGen has a very good page on it, with a lot of information gathered in one place. Things like this are valuable, because not everybody has the wherewithal or the know how to winnow scraps of information out of the corners of the Internet. 

There are two tests for vWD that can be carried out; the first is the "snap test", or , which is not a genetic test, but rather tests your dog's vWD factor that day. The blood's ability to clot varies on several factors that I know nothing about, and that test can assess in the moment whether there will be a difficulty in your dog's blood clotting during a surgical procedure. VetGen also has a genetic test, which will definitively state what your dog's genetic vonWillebrand's Disease type I status is: clear, carrier, or affected. According to VetGen, so far as Dobermans go, 25% (of the ones tested) are Clear, 49% are Carrier, 26% are Affected.

Clear obviously means that the dog does not carry a vonWillebrand's disease gene in any way. Carrier means that one of your dog's parents carried the gene, and thus the puppies in the litter (if the carrier was bred to a clear) have one half of the gene, but not the other. Affected means that your dog has vWD, but there are two parts to that: affected, and clinically affected. A clinically affected dog ought to have measures taken in order to ensure that she does not bleed excessively in the occasional of trauma or surgery. On VetInfo.com, two things that they suggest are having plasma on hand for a transfusion and cryoprecipitate which is a "frozen blood product prepared from plasma" according to the Wikipedia article. At least one more thing that goes without saying is not to administer a medication that's potentially a blood thinner, such as aspirin. 

Now, "clinically affected" means that the Doberman has both "halves" of the gene, and displays excessive bleeding symptoms, be it from surgery, trauma, or teething. An "affected" Doberman, though, carries both "halves" of the gene but may never present symptoms. This is hearsay, not clinical research that I've conducted, but I tend to trust the word of mouth from "my" Doberman people.

With some of the issues that Dobermans have, vonWillebrand's disease is not the most threatening of them; that one is Dilated Cardiomyopathy, which I'll discuss another time. It is not considered unethical in most circles to breed to a carrier; having a litter of carrier will not clinically affect them. vWD is one of those topics that a breeder who is less than ethical might dwell upon in order to cloud other issues in a buyer's mind; the vWD test is comparably cheap, at $75, to other health tests, and thus very accessible.

Edited to add: I revisited the VetGen page of tests by breed, and the VetGen vWD test is in fact $140. I apologize for providing incorrect information here.





19 comments:

  1. We hope Elka is OK now. Have a lovely day.
    Best wishes Molly

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    1. She seems just fine, thank you! Walks have returned to their regular schedule, and we no longer subject her to wearing the sock.

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  2. I had no idea! Great educational post!

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    1. Thank you!

      I certainly never heard of it until we started looking into breeders.

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  3. Glad to hear that Elka is not affected! I know when I lived with my Boxer girl, vWD was a concern for that breed too -- and there are others. Thanks for helping to inform people :-)

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    1. It's funny how much overlap Boxers and Dobermans have so far as health concerns go! vWD, DCM, hips and elbows (though I guess that at this point it's practically every breed....)

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  4. Kyuss is a carrier as well.

    "It is not considered unethical in most circles to breed to a carrier; having a litter of carrier will not clinically affect them."

    This is very much true, if you breed to a clear only. Sadly, many widely accepted "reputable" breeders still breed to carriers to other carriers (which gives each pup a 33% chance of being affected) or affected to carrier. (each pup has a 50% chance of being affected)

    Even if vWD isn't the death sentence it's made out to be, that still doesn't make it right to breed knowing you have a good chance of passing the defect onto each pup, in my own opinion.

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    1. I do question the ethics of deliberately breeding affected dogs, even it if is only a % chance of the progeny being affected. It just seems counterintuitive, and it seems like there are enough clear dogs that though the acceptable gene pool might be small, it's still workable.

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  5. I've heard of it before, and I know that it's a clotting disorder. Greyhounds can have it as well. I really liked your explanation about how the genes can affect the dog, though! It made the "why" of it a bit clearer to me!

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    1. I simplified it drastically, I'm sure, but explained it as I understand it, anyway! I didn't know that Greyhounds could have it as well. So many things affect our poor dogs!

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  6. Genetic problems like VWd show how challenging it is to be a responsible breeder.

    Honey's breeder was a nurse by training. I always felt she had a better understanding of the potential hip and eye problems of the Golden Retriever. And a greater commitment to making sure those traits were not carried on in her litters.

    It takes a lot of work to breed dogs to be healthy. I wish more people understood this.

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    1. I'm glad that Honey's breeder is health conscious about her dogs! I do wish that more people understood that this sort of thing needs to be a concern, as opposed to thinking that dogs are just little dollar signs on four legs.

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  7. So is VWd polygenic or single recessive inheritance? I know some Chessies have had this, but there is no test for Chessies as far as I know and I do not think it is common.

    Since most hip issues are polygenic I don't see how any breeder can make any representations as to the hips of the dogs they produce other than to try to make sure the parents are sound. Even then and even if you use sound dogs for many generations you cannot guarantee anything when it comes to hips. Most people do not understand this.

    Heck most people don't seem to understand polygenic inheritance period.

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    1. According to some of the information on VetGen, it's recessively inherited, in Dobermans at least. I think that the different types of vonWillebrand's Disease might have different types of inheritance? From the VetGen site:

      " (1) vWD in Doberman pinschers is a true clinical disease in which affected animals are predisposed to have abnormally (and sometimes fatally) prolonged bleeding times. (2) The Dobe disease is recessively inherited, contrary to what some previous research had suggested in the past. (3) Carriers are unlikely to have bleeding problems but affected (that is, homozygous mutant) animals are at a significant risk of serious bleeding problems, if they undergo surgery or sustain moderate trauma. Penetrance is *far* less important than was inferred from the dominant, incompletely penetrant model. (4) If this one mutant gene was eliminated from the breed, vWD would become a very rare disease, indeed, in Dobes."


      I am not a scientist, in biology or otherwise, so my understanding of some of these things is purely in a layperson sort of way. Hips are unfortunately not simple; so few things are. I do try to read about it, and get a base understanding, anyway.

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  8. Very interesting and informative. I was not aware that von Willebrand's affected dogs, but a good *human* friend of mine has it. Education is always a good thing, so thanks. :)

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    1. I never knew that it affected humans! I mean, I've heard of hemophilia, but that's it. It's funy how things like that can work out!

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  9. Hi - can you post this Blog at The Doberman Pinscher Community at vorts.com? Our members will love it!
    It's easy just cut and paste the link and it automatically links back to your website. You can also add Classifieds, Photos, Videos, etc. It’s free and easy…
    We are looking for contributors to share stuff with our members. Please help.
    Email me if you need any help or would like me to do it for you.
    http://www.vorts.com/doberman_pinschers/
    Thanks,
    James Kaufman, Editor

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