The notion that mixed-breed dogs are healthier than purebreds has some basis in fact, according to research published in the June 1 issue of the Journal of the American Veterinary Medical Association. Looking for 24 genetic disorders, UC Davis researchers flagged 27,254 dogs with inherited conditions out of 90,004 dogs checked.
A University of California, Davis, research team combed the records of 90,004 dogs seen at the university’s William R. Pritchard Veterinary Medical Teaching Hospital over a 15-year period ending Jan. 1, 2010.
Looking for 24 genetic disorders, the researchers flagged 27,254 dogs with inherited conditions.
Using healthy dogs as control subjects, the researchers discovered:
• No differences between purebred and mixed-breed dogs in regard to 13 genetic disorders, including hip dysplasia, hyperadrenocorticism (Cushing’s syndrome), hypoadrenocorticism (Addison’s disease), lens luxation, patellar luxation and cancers such as hemangiosarcoma, lymphoma, mast cell tumor and osteosarcoma.
• Purebred dogs were more likely to have 10 genetic disorders, ranging from dilated cardiomyopathy and elbow dysplasia to cataracts and hypothyroidism.
• Mixed-breed dogs had a greater chance of suffering a ruptured cranial cruciate ligament.
The researchers concluded that modern purebred dogs or members of similar lineages appeared to be more susceptible to certain inherited disorders. Disorders occurring equally among purebreds and mixed-breeds suggested that the disorders represented more ancient mutations and were more widely disseminated throughout the canine population.