For many years, it was a common belief that purebred dogs were far more likely to be unhealthy and subject to more disease than mixed-breed dogs or mutts. Thanks to two specific studies on this issue, as well as research being done by the AKC’s Health Foundation and Breed Clubs, this myth has now widely been disproved.
In 2013, the University of California-Davis published findings with the American Veterinary Medical Association (“Prevalence of inherited disorders among mixed-breed and purebred dogs”). Of the 24 disorders identified in the 27,000 dogs studied, 13 of those disorders showed that there was no significant difference in the rate of occurrence in mixed-breed vs. purebred dogs of the same age, weight, and sex that reported those illnesses. Genetic disorders were found to occur in at least 10 of the purebred dogs reporting to the study, which would make sense as the gene pool used to breed purebred dogs is significantly smaller than what occurs with a mixed breed. The study also found that mixed-breed dogs report being ill to emergency rooms at the same rate as purebred dogs, and that health problems such as cardiac issues, hip dysplasia, mast cell tumors, and lymphomas occur just as much in mixed breeds as purebred dogs.
The most recent study on this topic was conducted by the Dog Aging Project and published in 2024 in Frontiers in Veterinary Science. This study found that of the 27,541 dogs studied, some of the most common reasons dogs go to the vet have nothing to do with breed at all. The study included 25 different breeds of purebred dogs, and the top ailments they suffered were dental calculus, bites from other dogs, extracted teeth, osteoarthritis, and Giardia. Meanwhile, mixed-breed dogs’ top reported ailments were torn/broken toenails and chocolate toxicity. However, of the 53 medical conditions identified, 26 were found to affect purebred and mixed breeds equally. The conclusion was that breeding alone was not the most significant factor in health. Diet, lifestyle, and individual genetic makeup were equally important factors in overall health.
The AKC Health Foundation, along with purebred dog clubs, has spent millions of dollars identifying genetic diseases in various breeds of dogs. For example, a genetic disorder called Lethal Acrodermatitis, or LAD, was at one time common in Bull Terriers. LAD, or “zincers” as we called them, is a serious condition that can be fatal in puppies that involves an immunodeficiency that results in lesions and serious skin disorders. With help from the AKC, the gene that causes this condition was identified. Now, a DNA test is available to breeders to rule out if a dog is a carrier of the LAD gene. Before I breed, I have all of my Bull Terriers tested to exclude LAD carriers from my breeding stock. Nearly every other breed that I am familiar with has a list of genetic diseases that a breeder should test for before doing a breeding. If you are looking for a purebred dog, you should always, always, always check with the AKC parent club of that breed for a list of those issues and ask breeders if they health-test.
I believe that everyone who wants a dog should feel free to get whatever dog will make them happy. Both of these studies show that whichever road you want to take when bringing a dog into your life, be prepared for the dog to, at some point, be sick and need vet care.
If you have any questions, please feel free to email heidi@fouronthefloordogtraining.net.
Heidi Clayton started Four On the Floor Dog Training to provide positive, reward-based dog training in South Jersey. She breeds, trains and shows bull terriers under the SoraBully’s Bull Terriers kennel name. Email questions to heidi@fouronthefloordogtraining.net or learn more at https://fouronthefloordogtraining.net
