Have you heard the claim that purebred dogs have more health problems than mixed breed dogs? Is it true, or is it just a myth?
How to identify a purebred
A dog is defined as purebred if he or she has been registered with a Kennel Club and has papers to prove that the mother and father are both of the same breed. If the papers show that a dog’s ancestors all come from the same breed, then that dog is considered to be a pedigreed purebred dog.
Purebred dogs are a product of selective breeding by humans. Dogs from the same breed are chosen for their genetic traits, such as size, temperament, coat type and colour, and then bred together.
Mixed breed and hybrids
In contrast, mixed breed dogs (aka mutts) are defined as the offspring of dogs that are not from the same breed and usually have unknown ancestry. But there is another category you might not have heard of—hybrid dogs.
A hybrid dog is the intentional offspring of two purebred dogs from different breeds. Usually hybrids are the offspring of a purebred Poodle and something else, and the offspring can have fantastical names, like Goldendoodle, Maltipoo or a Saint Bernadoodle. Some breeders are taking it one step further, crossbreeding hybrid dogs to create second-, third- and fourth-generation hybrids.
Are mutts healthier than purebreds?
If you ask any mutt parent if they think that mutt dogs are healthier than purebreds, they will usually say yes, because there is more diversity in a mutt’s gene pool. But if you ask a conscientious breeder the same question, however, they will tell you that because of genetic testing, inherited disease testing and temperament testing, a purebred is healthier.
As far as I can tell, there are no studies that back up either claim, so everything I have to share on this topic is based on 16 years of clinical practice experience. Generally speaking, I think mixed breed dogs tend to be healthier and tougher and tend to live longer than many of the purebreds I see in practice. Mutts, in my experience, tend to have lower incidences of inherited disease, such as some cancers, back problems and hip dysplasia.
Why do some purebred dogs have health problems?
When you purchase or adopt a purebred dog, you are getting a dog that has less genetic diversity than a mixed breed dog. This is not necessarily a bad thing, if the breeder has done her due diligence in making sure to sell puppies that are free of genetic diseases.
In a perfect world, every purebred puppy bought on this planet would be well-socialised and cared for before being adopted, and certified to be free of any genetic diseases. The reality, however, is that disease testing and proper socialisation take time and money, and purebred puppies that are sold responsibly cost a lot more than puppies sold from a backyard breeder or a pet store that is selling puppies sourced from an unethical puppy mill.
I have seen many heartbreaking situations where people bring in their purebred puppies for their first health checkup, only to find out that the puppy has one or more genetic diseases that weren’t detected or even tested for by the breeder or pet store.
Why more popular purebreds are more at risk
Not all purebred dogs have the same trouble with inherited disease. In general, the more popular a breed is, the more likely it is to have problems due to inbreeding or unethical breeding for profit purposes.
Labrador Retrievers and Golden Retrievers are very popular family pets and are more likely to be afflicted in inherited disease conditions like skin allergies, ear infections and hip dysplasia. Pugs, Bulldogs and other short-nosed breeds are also very popular, but unless they are carefully bred, can develop all sorts of inherited problems, such as heart disease, dental disease, skin problems and breathing problems.
I’m not saying that a mixed breed dog won’t have any of these problems, but when you increase genetic diversity through breeding different breeds together, then there is a better chance of winning the genetic lottery and having lower incidence of genetic disease.
Avoiding health issues with purebred dogs
You can avoid purchasing a purebred or hybrid puppy with genetic diseases by only buying from reputable breeders who test for genetic diseases that are common in the puppies they are breeding. You will pay more for puppies that have been certified to be disease-free, but the old adage holds true here: You get what you pay for.
If you have a mixed breed dog and you want to know the genetic ancestry and any potential genetic diseases that he or she may be predisposed toward, chat with your vet.
Knowledge is power, and knowing your dog’s genetic ancestry and markers for disease allows you to make lifestyle changes early so you can hopefully prevent disease.
By Dr. Sarah Wooten, DVM