von Willebrand's Disease (vWD)
vWD is a blood disorder, a deficiency in clotting factor VIII antigen. This substance is called "Von Willebrand's factor". Dogs affected by the disease do not effectively utilize their platelets for blood clotting and therefore are more likely to have excessive bleeding episodes upon injury. This is similar to hemophilia in humans.
vWD is a common inherited disorder. Certain breeds, including German Shepherds, have a higher than normal incidence of this disorder.
The main symptom of vWd is excessive bleeding, generally occurring after an injury or surgery. Dog's with Von Willebrand's disease may also develop nosebleeds or bleeding from the gums; bleeding in the stomach or intestine may also occur; and some dogs may have blood in their urine. Symptoms similar to those of arthritis may also occur if bleeding is into the joints.
Full information can be found at this link Pet Education - von Willebrand's Disease.