Dog breeds like French bulldogs, pugs, and dachshunds may be suffering from an overdose in cuteness. Essentially, selective breeding for the traits that makes them popular is making it harder for some of them to live normal lives.

“It’s truly incredible what people have done with really what is supposed to be our companion,” says Enid Stiles, a veterinarian in Montreal who has been practicing for more than two decades. “Unfortunately, we have managed to totally mess them up.”

What Is the History of Dog Breeding?

All dogs originally descend from wild wolves, which were domesticated over a long period between 15,000 and 30,000 years ago. The transition from competitors to pets wasn’t always a smooth one, though, as humans often ate these pets in the early days of domestication.

What Is Selective Breeding?

Once dogs started becoming more of a fixed element in human societies, people began changing their shape through selective breeding. In this early period, these changes were often made to fulfill a function — their size bulked up in parts of Europe between 8,000 and 2,000 years ago, for example, to help protect livestock from their wild counterparts and other predators.

But by Roman period, evidence shows that our canine companions started to shrink, with lapdogs becoming more popular. Indeed, scientists used radiocarbon dating on a 2,000-year-old skull to determine that Romans may have been among the first to deliberately breed lapdogs, according to a study published in the Journal of Archeological Science in 2023.

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How Does Selective Breeding Work?

Dog breeding to encourage certain traits is conducted over generations. If you want size, for example, then you try to breed the biggest males with the biggest females. From the litters produced, you again select the biggest individuals and breed them together.

Female adults produce about a half dozen puppies on average per litter every 6 to 8 months, and reach sexual maturity after 1.5 to 2 years. In short, it doesn’t take too long to start seeing changes in a breed.

“It’s the good and the bad of breeding dogs,” Stiles says. “You can see good changes quickly, but you can also see detrimental changes quickly.”

Read More: 5 Dog Breeds That Have Changed Over The Past 100 Years

How Can Breeding Cause Health Problems?

Selective breeding doesn’t always cause a huge problem, especially if it has happened over a long period of time, as with many older breeds of dogs. One problem occurs with genetic bottlenecks, when just a few dogs are overused to produce litters. This often means many of them are inbred as siblings, cousins or other close relatives are bred together to select for desired traits.

But even when they aren’t closely related, the desired traits themselves can cause problems. One trait that has caused a number of issues is a flat faces with a small nose — a characteristic of breeds like pugs, and English and French bulldogs known as brachycephalic breeds.

As these pups’ snouts have gotten shorter, it has affected their ability to breathe through their noses. Many French bulldogs and pugs can only take in air through their mouths. But while their mouths may be smaller than wolves, their palates remain relatively large, which means that even mouth breathing is partly occluded.

“You can hear it,” says Stiles, who is chair of the Animal Welfare Working Group of the World Veterinary Association.

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What Other Issues Can Selective Breeding Cause?

Breathing problems can lead to a number of other problems in these brachycephalic breeds. For example, they can have trouble with heat and physical exercise since they can’t take in enough oxygen to fuel their activity. The heavy panting can lead to excessive work on their abdomens, which can lead to hernias and other issues over time, Stiles says.

“I love these dogs, they are beautiful little doggies,” she says. “But they can’t breathe, and as a result they have so many other problems.”

Furthermore, while their mouths have been shorted by selective breeding, all adult dogs still have 44 teeth. This isn’t always a problem for breeds with big snouts like German shepherds, but pugs and French bulldogs often have dental issues as a result of all these teeth competing for space in their mouths.

For example, teeth can get stuck in the gums, or get rotated in their mouths as they try to squeeze into a smaller space. These issues can lead to chewing problems and infections in many brachycephalic breeds.

What’s more, breeds like pugs or bulldogs with small or twisted tails can also have back problems as a result of selective breeding.

Read More: Why Taking Your Dog On A “Sniffari” Will Tire Them Out More Than A Walk

What Are Some of the Most Unhealthy Dog Breeds?

Cuteness, which is arguably why dogs like pugs, French bulldogs, cavalier King Charles spaniels, and English bulldogs are bred to have flat faces, is one problem. But other issues based on appearance also affect breeds like German shepherds and dachshunds.

Dachshunds

Wiener dogs, or daschunds, have been bred to have short legs and long bodies. Originally, this kind of selective breeding was to create canines that could attack badgers in their holes — in fact, the German name ‘dachshund’ translates to ‘badger dog.’

But breeders have been selecting for longer backs and shorter legs over time. These traits can be a problem when jumping down from couches and car seats, or using stairs, leading to issues like prolapsed discs: the Universities Federation for Animal Welfare in the U.K. estimates that about a quarter of dachshunds experience disc damage in their spines at some point in their lives.

In the worst of cases, dachshunds can even be paralyzed due to back injuries.

German Shepherds

German shepherds, on the other hand, have been bred in recent decades to have increasingly sloped backs so their shoulders are much higher than their hips.

“I guess it makes them look quite regal,” Stiles says.

However, this sloped appearance can lead to issues with their hips such as degenerative myelopathy — a condition that begins with weakness in limbs and can progress to paralysis of both hind legs.

Read More: 10 of the Cutest Dog Breeds to Tug on Your Heartstrings

Why Do We Still Continue to Breed for Cuteness?

Surely, since we have gotten our pets into this issue, we can get them out again using similar techniques in selective breeding. But the problem is ongoing, as breeders continue to select for cute traits that don’t always lead to healthy puppies.

Part of the problem is the standards set by the notions of what constitutes a pure breed. These notions aren’t as clearcut as many think — they are often set by breeders clubs and dog competitions, where individuals from certain breeds are often awarded for the exact same characteristics that are causing health problems.

Some of the national kennel clubs — or registries of purebred breeders — are working to change these standards, Stiles says, but they can’t control everything.

Beyond that, social media posts on Instagram or Facebook often propagate the popularity of many of these breeds; French bulldogs were the most popular dog breed in 2022, according to the American Kennel Club.

Read More: 5 Unusual Ways That Dogs Help Humans

How Can People Help Their Pets?

Ultimately, prospective pet owners drive the interest in these breeds. At her vet practice, Stiles often sees dachshund owners reluctant to pay for back surgeries, or Frenchie owners reluctant to get their pet’s breathing problems fixed despite paying hundreds of dollars or more for their pets.

In other cases, people don’t even see the breathing troubles as a problem. “People think that it’s funny that they are snoring, [or] that they are snorting when they are walking,” Stiles says of brachycephalic breeds.

One step that helps is to use ethical, reputable breeders. But even this can’t correct for everything, and she doesn’t think that certain brachycephalic breeds should be permitted. “I don’t think they should exist in the current status they have,” she says, adding that cavalier King Charles spaniels and English bulldogs have been banned in Norway as a result of their poor genetic health.

The International Collaborative on Extreme Conformations in Dogs, an international multi-stakeholder group “committed to welfare-focused breeding, ownership, and promotion of healthy conformations in dogs,” says that selective breeding for certain traits should never restrict them from normal activities.

“All dogs, regardless of role, type, breed or cross breed, should be able to experience good innate health that enables these dogs to perform all of the activities necessary for their health and welfare within the anatomical, physiological and behavioural evolutionary norms for the species, and the dog’s stage of life,” the group said in a statement.

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