A moderately severe expression of classical hemophilia in a family of german shepherd dogs.

A kindred of German shepherd dogs with a moderately severe form of classic hemophilia was studied. The propositus was presented at five months of age because of a persistent hind limb lameness and swelling of the left stifle joint. Unclotted blood was aspirated from the swelling. A brother of this dog's dam had been diagnosed as a hemophiliac.Hemostatic tests were performed on the propositus and on ten available related dogs. On the basis of pedigree analysis, sex and specific factor VIII related activity levels in their plasmas, the dogs were classified as affected, carriers, or unaffected. The propositus and one male relative were identified as classical hemophiliacs and were classified as moderately severely affected on the basis of apparent bleeding tendency and factor VIII procoagulant levels (FVIII:C 8-10% of normal). The propositus' signs were confined to those of lameness and joint soreness and postmortem lesions were confined to a few joints (hemarthrosis). The affected male relative was asymptomatic up to the time of euthanasia (three months of age) and did not have postmortem lesions attributable to hemophilia.Although classic hemophilia (particularly in large breeds of dogs) is often a severe clinical disease, more moderate forms of the disease do occur. Such forms may be more difficult to recognize early in life.