Mutts appear healthier, but only by a cold, wet nose

Are mutts the smartest and healthiest pets?

A new study of the medical records of more than 90,000 purebred and mixed-breed dogs suggests that there is some truth to this conventional wisdom on canine health - but only to a point. When it comes to genetic disorders, a Maltese isn't always more likely to suffer than a mongrel.

Veterinary researchers at the University of California-Davis reviewed the medical records of 90,004 dogs evaluated between 1995 and 2010. They identified 27,254 dogs with at least one of 24 genetic disorders, including cancers, heart and endocrine disorders, and orthopedic problems. The rest of the dogs were controls.

They found that 13 disorders were equally common in both purebred and mixed-breed dogs, including all of the cancers and hip dysplasia. Ten disorders, including cataracts and epilepsy, were more common in purebred animals; a knee injury called cranial cruciate ligament rupture was more likely to strike mutts.

Disorders that appeared equally often in both groups of animals, the researchers suggested, may have resulted from mutations that arose in their common, distant wolflike ancestors.

The study was published Tuesday in the Journal of the American Veterinary Medical Association. - Los Angeles Times