Big, strong, full of heart but also of brains, Dobermanns are giants of the dog world. If you’re in the market for a Dobermann and researching your options, or just learning more about your own Dobermann, you might have seen references to Dobermanns bleeding. What does this mean? Why do Dobermanns bleed? Should you be worried?
Table of contents
Bleeding and Clotting
Before we get into Dobermanns specifically, let’s discuss bleeding and clotting in all dogs.
When an animal is wounded, blood vessels are damaged resulting in bleeding. If this continues an animal could lose too much blood and bleed out. To stop this a blood clot will form to plug the bleeding hole. There are three stages to blood clot formation.
The first stage, known as primary haemostasis, is the initial response.
When blood vessels are damaged, they release chemicals that attract clotting factors circulating in the blood. Platelets bind to the damaged blood vessel, specifically to collagen and a chemical called von Willebrand’s factor (VWF). This plugs the gap, like filler in a nail-hole, creating a blood clot. Fibrinogen, another clotting factor, will bind to the platelets, making them stick together to form a cohesive mass. The blood vessels will also constrict to reduce blood flow to the bleeding area.
The secondary stage is where the blood clot strengthens.
This involves several coagulation factors, such as factor VII. Most require vitamin K and are manufactured in the liver. The factors convert the fibrinogen into stronger fibrin, making the clot stronger while the blood vessel heals. The clot may last only a few hours or several weeks if the wound is large.
Finally, the tertiary stage is the breakdown of the clot once the damage has been healed.
Plasmin breaks down the fibrin, dissolving the clot. Underneath, the healed blood vessel tissue can start to function as normal.
A disorder at any stage of the clotting process can result in failure of clot formation (if the disorder is primary or secondary) resulting in bleeding and blood loss, or inappropriate clot formation (if the disorder is tertiary) resulting in thrombi and blocked blood vessels.
Dobermanns and von Willebrand’s Disease:
Von Willebrand’s disease (VWD) is a congenital genetic disorder of primary haemostasis, involving von Willebrand’s factor (VWF).
What that means is that animals with VWD have an issue with their VWF, resulting in problems forming blood clots in the first place. Reduced or defective VWF results in platelets not being able to bind to damaged blood vessels properly, preventing clot formation. Animals with type I VWD have reduced but functional VWF, those with type II have defective VWF, while those with type III have no VWF. VWD is the most common bleeding disorder in dogs.
Dobermanns are a breed of dog where VWD has been commonly identified. They tend to get type I VWD. Other dogs prone to VWD include Bernese Mountain dogs, Poodles, Corgis, German pointers, Scotties, and Shetland sheepdogs. It has been identified in pigs, mice, and possibly other animals too.
In all cases, VWD is a genetic disorder an animal is born with
There is a gene that results in defective or reduced production of VWF. If a dog has even a single copy of this gene, they have some degree of VWD. Dogs with both copies of the gene tend to have more severe signs (they carry only 10% VWF compared to 50% with just one gene, because the effects of the bad gene aren’t “diluted” by having one functional copy). This means that the genes of a parent dog can be tested to determine the likelihood a puppy will have VWD (more on this later). Any dog with even one VWD gene has the potential to pass on VWD to their puppies.
The incidence varies. One study from 1995 reported 373 of 614 Dobermanns (60.7%) had VWF levels less than 50% of normal, and 107 (17.4%) had bleeding events. A genetic testing company found that 49% of Dobermanns tested in the USA had at least one copy of the defective gene and 25% had two copies, thus the more severe form of the disease. So on average, based on these studies, over half of all Dobermanns probably have some form of VWD.
Symptoms
The symptoms of VWD tend to be milder if it is type I, and severe if it is type III.
The most common are prolonged bleeding and slow clot formation. Dogs that cut themselves will take a long time to stop bleeding and are at greater risk of losing a lot of blood. Owners may notice this and report it to their vet, especially if they cannot stop the bleeding at home. Entire female dogs may also bleed excessively during their season.
There can also be spontaneous or random bleeding without any cause, such as nosebleeds, blood in the urine or faeces, gum bleeding (especially in puppies growing new teeth), or bleeding into the eyes. Dogs may also be more likely to bruise, and the bruises can be more severe. Very rarely, and generally with more severe VWD, dogs can bleed internally.
If blood loss from any site is excessive, dogs may become weak, unwell or even sick, collapse, have seizures or enter comas, and can die if the loss is severe. Any sudden, uncontrolled, or prolonged bleeding could be an emergency and should be dealt with by a vet.
Diagnosis
Diagnosis of VWD can be difficult, and a dog may go years (or even a lifetime) without being diagnosed. We often are only suspicious of VWD if a dog is brought in with an episode of bleeding or they bleed excessively and prolonged during a routine surgery.
Clues to VWD are symptoms matching a primary haemostatic disorder, but a normal platelet count and appearance, and a prolonged bleeding time – we can quantify this with buccal mucosal bleeding time (BMBT), where we make a small cut into the gums and measure how long it takes to stop bleeding. A healthy dog should bleed for 4 minutes or less (usually quite a lot less in practice!). However, this can be risky to perform as a dog with VWD will bleed excessively from the gums, possibly even resulting in dangerous blood loss.
There are only two definitive ways to diagnose VWD. The first is to perform a specialist blood test (an ELISA). This detects the concentration of VWF in the blood – if it is low, it raises suspicion of VWD. The second is a genetic test on a blood sample – this test will identify the defective VWD genes, and the number. If a dog has one or two of the genes, they have VWD.
Treatment
There is currently no specific treatment for a dog with VWD, as it is a genetic disease that cannot be removed from a dog’s DNA. Treatment for active bleeding may involve prolonged pressure, a whole blood transfusion from a dog with plenty of VWF, a transfusion of plasma, desmopressin (a drug to increase release of VWF if the dog has type I VWD) and preventing movement that can cause further clot agitation.
If a dog with VWD needs surgery for any reason, we will often discuss blood transfusions before surgery – not to replace the blood cells, but to ‘top up’ their VWF levels.
Prevention
The best way to prevent (and in the future stop entirely) VWD is via safe regulated breeding with genetic testing. As VWD is a genetic disorder inherited from the parents, we can test every Dobermann via a saliva or blood sample before they breed. We can even test puppies, meaning we can easily identify those that have normal genes and can safely breed later in life, and those which have one or two copies and should never breed.
Because so many Dobermanns carry the genes, breeding from such a small pool of healthy individuals could lead to increased inbreeding and a greater risk of other genetic diseases. Thus, in some cases, it may be safe for a Dobermann with a single copy of the gene to breed with a Dobermann with no copies – there is a one in two chance each puppy will inherit a gene, but they cannot inherit two copies and have the more severe form of the disease.
Both the UK Kennel Club, as well as many vets, will be able to contact a laboratory who can perform this test for you. If you are considering breeding Dobermanns, we highly recommend you perform genetic testing first on both parents and avoid breeding if there is evidence for VWD. If you are looking to buy a Dobermann, ensure the breeder has performed genetic testing first.
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