What Qualifies a Dog as a Purebred Dog?
A dog is defined as purebred if he or she has been registered with the American 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 color, and then bred together.
Crossbreed and Purebred Dogs
Firstly, what actually is the difference between a crossbred and a purebred dog? We’ve spoken about this before. In the late 1800s, it became fashionable to show dogs at competitions. So it was necessary to start regulating and categorising dogs into different standard breeds for judging. This became the basis for the UK Kennel Club.
Today, purebred and pedigree dogs must be bred from parents of the same breed – to be a purebred Dalmatian, both parents have to be pure Dalmatians. Pedigrees have ‘proven’ lineage with the UK Kennel Club. But for even the most pedigree dog, its lineage is only on record as far back as the UK Kennel Club was formed; all dogs are of the same species and share many of the same genes from common ancestors. Nevertheless, purebred and pedigree dogs are generally bred from a very small population (we can’t grow this population, or the purebred/pedigree label would be lost) which means very little diversity, often leading to problems. More on this later.
On the other hand, crossbreeds are what they sound like – a mix of different breeds. Mongrel, mixed breed, mutt: these are all terms for a crossbred dog. One of the most well-known is the cockapoo. There is no standard definition, but crossbred dogs are generally intentionally bred to be of a certain mix (like cockapoos). Whereas mongrels are just mixes with no specific desired outcome. But the long and short of it is if a dog has multiple breeds in its lineage it is a mixed breed dog.
What are common mixed breed dogs?
It is difficult to pinpoint the most common mixed breed dogs, mainly because it is often difficult to identify what dog breeds exist in an individual dog’s history. That being said, you may notice that in many shelters a large portion of the dogs are labeled as Pit Bull or Pit Bull mix.
¿Does the MIXED BREED DOG Have an Advantage Over the PURE BREED DOG?
Is your dog purebred or a mutt? And what could that mean for his health and longevity?
Do you believe purebred dogs are more prone to genetic disorders than mixed breed dogs? Are mixed breed dogs healthier?
Some people claim that breeders who select for specific traits … can cause more frequent genetic disorders in purebred dogs. They talk about hybrid vigor in mixed breeds.
Hybrid vigor means greater health and resistance to disease. We’ll get into that in more detail in a bit.
And we’ll tell you about a huge 15-year study at University of California-Davis (UC-Davis). The researchers studied 27,254 dogs with inherited disorders to find some answers.
They theorized that since all domestic dogs come from three to five wolf lineages … you might expect dogs’ common ancestry to create disorders common to all breeds.
So read on … the results may surprise you! And they might give you some insight into your dog’s health and longevity potential.
Hybrid vigor is a term used in all kinds of breeding … not just for dogs. Even plants! It’s also called heterosis. The dictionary definition is …
And designer breeds … like goldendoodles, yorkipoos, puggles (the list is almost endless) are ever more popular.
So breeders of these dogs are jumping on the hybrid vigor bandwagon. They’re all over the internet … claiming the practice of combining breeds increases hybrid vigor.
A mule is an example of a true hybrid … a mix between a horse and a donkey. Or a “liger” … a lion and tiger.
In fact, when you cross two breeds, you can double up on health issues. This is especially likely when you have the same disease tendency in both breeds.
Anita Oberhauer PhD was on the UC-Davis research team. Here’s what she says about the labradoodle, for example …
The demand for these mixes means they’re bred indiscriminately. And health issues in these designer breeds abound. And of course, when “mutts” happen accidentally … there’s no planning involved. So you can’t predict likely health issues.
What matters more in healthy dogs is the size of the gene pool for the breed.
Some ancient breeds go back about 500 years. And they’re said to be healthier … because that means they have a larger gene pool.
Less popular breeds have smaller gene pools. A breed with a smaller gene pool would be more likely to have a recessive disorder. That’s because there’s less genetic variation.
Before this study, most researchers looked at single disorders … and their tendency in specific breeds.
So they looked at the prevalence of inherited disorders in the dog population as a whole.
They excluded non-domesticated canines like dingoes or wolves. And they viewed Pit Bulls separately. (Because it was hard to confirm their purebred status.)
The control dogs came from healthy dogs at the teaching hospital during the study period. The researchers classified healthy dogs by …
Then they matched these dogs to each affected dog for the disorders … and randomly selected the control dogs for each disorder.
From 1995 to 2010, the researchers studied 27,254 dogs with inherited disorders at the University of California-Davis Veterinary Medical Teaching Hospital.
The theory that purebred dogs are more prone to disease doesn’t really hold up. Let’s look at some numbers.
… more than half (13) were about the same in purebred vs mixed breed dogs (matched for age, sex and body weight).
Every disorder was seen in the mixed-breed population. But in this study … only one disorder was more likely in mixed-breed dogs than purebred.
That one disorder was cranial cruciate ligament rupture. And it was significantly higher … 30%. The researchers didn’t really know why this might happen. It’s possible combining different physical conformations reduces the resilience of the ligaments.
The researchers remind us that this study evaluated dogs in a teaching hospital. That could have skewed the results because ….
So a condition may get diagnosed at a higher rate than it would in the broader population of dogs. This would mean the study caused overrepresentation of some problems in purebred dogs.