Haemophilia A in German shepherd dogs.

Haemophilia A was diagnosed in 14 male German shepherd dogs. Factor VIII: coagulant (FVIII:C) activities ranged from 1.13% of a normal canine plasma pool. von Willebrand's factor antigen values were normal or increased in all 9 of these dogs which were tested. Twelve of these dogs had a common maternal grandsire. Five dogs had exhibited no tendency to bleed (when tested between 2 to 23 months of age). They were tested because of pedigree links with clinically affected animals. Common clinical signs in the latter dogs included: bleeding from the mouth, subcutaneous and intramuscular haematomas and lameness. Since these dogs usually had a mild to moderate deficiency of FVIII:C, they may survive to adulthood without exhibiting clinical signs severe enough to necessitate veterinary attention.