Inbreeding puts dogs at risk of birth defects and genetically inherited health problems. ... However, the defect may become common in later generations if his grandpuppies and great grandpuppies are mated with each other, rather than introducing new genetic traits by breeding outside their relatives.

Can inbreeding cause problems in dogs?

The extent of inbreeding in purebred dogs and how this reduces their genetic variation is revealed in a new study by Imperial College London researchers. Inbreeding puts dogs at risk of birth defects and genetically inherited health problems.

What problems do inbred dogs have?