Common Diseases
Cavaliers can suffer from a number of severe genetic defects. Two possible genetic conditions, mitral valve disease and syringomyelia, can be both severe and very common. It is very important to adopt Cavalier puppies from a reputable breeder- found through national dog clubs- who screens all their breeding dogs for these conditions. Breeders who breed for health will willingly supply heart, hip, eye, and patella clearances for their breeding dogs, and responsible breeders choose pairings to try to reduce the incidence of all these defects in the breed.
Mitral valve disease
Virtually all Cavaliers eventually will suffer from mitral valve disease. This condition is polygenic, and therefore all lines of Cavaliers worldwide are potentially susceptible. It is the leading cause of death of the Cavalier King Charles Spaniel, and the reason the Cavalier's expected lifespan is only between seven and ten years.
Syringomyelia
Syringomyelia (SM) is a condition affecting the brain and spine, causing symptoms ranging from mild discomfort to severe pain and partial paralysis. It is caused by a malformation in the lower back of the skull which reduces the space available to the brain.
Syringomyelia is rare in most breeds but has become widespread in the Cavalier King Charles Spaniel. Symptoms of syringomyelia typically appear between six months and four years of age. Symptoms include sensitivity around the head, neck, or shoulders, often indicated by a dog whimpering or frequently scratching at the area of his neck or shoulder.