Von Willebrand's Disease (Type 3) - vWD (Type 3)
OverviewvWD is the most common canine coagulation abnormality, it is a blood clotting disorder that results in various levels of bleeding in affected dogs. In affected dogs, the platelets or blood cells that normally act as a barrier against excessive bleeding are ruptured. This abnormality in the blood cells is attributed to a genetic mutation for the glycoprotein von Willebrand Factor (vWF) in the blood. · Type III is the most severe form of vWD, type III affected dogs have essentially no plasma vWF and will suffer the most severe bleeding of all affected dogs.
Severity - 5
Type III vWD has an extreme degree of severity.
Excessive bleeding is the most important and often distressing symptom. Bleeding generally occurs after a wound or surgery, in affected dogs the blood does not clot in the normal time and the bleeding is extensive.
Affected dogs may also suffer nosebleeds and bleeding from the gums. Bleeding can also occur internally in the stomach or intestine, in which case the dogs stool may contain blood. In some cases blood can also be detected in an affected dog’s urine.
It is important that suspected dogs be tested as unknown affected dogs can bleed to death following surgery, or what would normally be non-life threatening injuries.
Animal Network provides a DNA test that determines the genetic predisposition to vWD.
Von Willebrands Disease (vWD I II III) is an autosomal recessive disease. A recessive phenotype (trait or disease) will only be expressed when two copies of the recessive gene variant are present. A direct gene test can detect whether a dog is clear, carrier or is affected by the disease.
A dog with two copies of the recessive gene variant is affected, they will express the phenotype and will pass a copy of the gene variant onto their offspring 100% of the time. A dog with one copy of the recessive gene variant is a carrier, they do not express the phenotype themselves, however they are will pass the gene variant onto their offspring 50% of the time. A dog that has does not have any copies of the recessive gene variant is clear, and will never produce affected offspring.
For an explanation of possible genetic status of offspring please refer to our fact sheet on Breeding strategies. ORDER A TEST
Breeds AffectedScottish Terrier
Shetland Sheep Dog