Hemophilia B (canine, F9-related)

Canine hemophilia B is a rare X-linked bleeding disorder reported in multiple breeds (e.g., Hovawart family with Leyden-like phenotype, experimental colonies). Large, population-based incidence data for pet dogs are lacking. Human severe hemophilia B affects ~1 in 25,000–30,000 male births, with persistent excess mortality and morbidity despite modern care (PAPER-07, BIOMNI-05).