Author: Tracy Reis, DVM
For a long time, it has been believed that most mutts are healthier than purebred dogs because of their mixed genetics from several breeds. Recently, a study was published indicating that this may not necessarily be true. The new study of over 90,000 purebred and mixed-breed dogs suggests that genetic disorders may not always be more prevalent in a Maltese than a mutt.
The specific conditions studied included cancers, heart and endocrine disorders, orthopedic problems and other diseases. The conditions were selected because they could be diagnosed accurately.
When the researchers assessed the prevalence of each of the genetic conditions in purebred versus mixed-breed dogs, they found that as many as 13 of the diseases were just as common in purebred dogs as in mutts, including all of the cancers and hip dysplasia. There were 10 disorders, including cataracts and epilepsy, found more often in purebred animals, and one, a knee injury called cranial cruciate ligament rupture, was more likely to strike mutts.
A non-genetic problem more prevalent in mutts was being hit by a car. This is because there are more strays or homeless street dogs that are mixed breed than purebred dogs.
Disorders that appeared equally often in purebred and in mixed-breed animals, the researchers suggested, may have resulted from mutations that arose long ago, for example in some dogs’ distant ancestors like early wolf progenitors. Such early mutations would be common in the dog population at large, they wrote, adding that “perhaps the same desired traits that made dogs a favorable species for domestication were linked” to the diseases that seem to appear at similar rates in all kinds of dogs.
The mutations that cause disorders more common in purebred animals, on the other hand, probably emerged more recently from common ancestors that all dogs in a particular breed, or group of breeds, would share.
While these are the results of a recent study, there are still breed specific diseases that can run in lines. Every year the AKC Canine Health Foundation (CHF) polls breed parent clubs about their top health concerns and research interests. The primary purpose of this poll is to give researchers information about the health priorities of each of the parent clubs. A secondary purpose is to provide prospective pet owners with information that indicates what diseases affect each breed or are of greatest concern to owners of a breed. It is important to remember that any dog can come down with a particular disease. Furthermore, any dog can be very healthy throughout life, regardless of specific diseases that are listed as concerns for the breed.
Whether you are thinking about getting a specific breed or just looking for a great pet, do your research. If using a breeder, do as much research as possible on the line your new puppy is coming from; you should be able to see the parents. Good breeders generally focus on one specific breed. If you are set on a specific breed, there are also a lot of purebred dogs in shelters, as well as breed specific rescue organizations. Never buy a dog from a pet store, since these dogs come from puppy mills and, regardless of breed, are more likely to have health problems because of inbreeding, poor care early in life, and being separated from their mothers too soon. You are also helping to perpetuate the horrible conditions that the breeding dogs live in at these puppy mills. Any dog that comes with papers from the USDA is a puppy mill puppy. So do your research first, that way you will end up with the right dog for you and your lifestyle.