Pedigree of inbred GSDs with platelet procoagulant deficiency.

Solid symbols represent dogs with clinical signs of bleeding and high residual serum prothrombin; shaded symbols represent dogs with high residual serum prothrombin (but no history of abnormal bleeding); open symbols represent clinically normal dogs with normal residual serum prothrombin; U indicates dogs unavailable for testing. Arrows indicate the 5 dogs examined in this report.