Hemophilia in a Great Pyrenees.

A case of hemophilia A in a male Great Pyrenees puppy is described. The animal initially had a soft tissue mass on the forehead and later developed a hematoma in the shoulder area and gingival bleeding. Coagulation studies revealed normal bleeding and prothrombin times, prolonged clotting and activated partial prothrombin times and decreased factor VIII activity. The dam and a female littermate also had decreased factor VIII activity and were probably carriers of the disease.