Centuries of inbreeding has left the English bulldog in a bad place

Unable to breed without intervention, prone to infections and exhaustion, to survive, the bulldog might have to change

English Bulldog, BioMed Central

[Flickr/michal adamczyk]

The English Bulldog might well be the ideal dog for many families, but the breed has become riddled with health problems. From breathing issues to skin disorders, new research into the stout canine has concluded that the only way to successfully breed these problems out of the dog is to introduce some new genetic diversity.

The first noted descriptions of the English Bulldog date from the 1630s, but contemporary specimens are wildly different from what we expect in the species today, to the point of being likely unrecognisable. In the centuries since, dog breeders have encouraged the development of specific physical traits through rigorous selective breeding. In the race for shorter skulls, smaller tails, and more skins folds in the face, some breeders have even resorted to inbreeding, mating genetically related dogs for their desired traits.

This hasn’t been good for the bulldog, which was not the healthiest canine to being with. Due to their squat build, the dogs can rarely breed without artificial insemination. When puppies are born, bulldogs experience a significantly higher rate of puppy mortality and birth defects. Those that make it to adulthood have to deal with a tongue that is larger than their mouth, making breathing difficult and causing excessive panting when exercising, which can lead to overheating. The folds of their skins are prone to developing sores and abscesses. English bulldogs have an expected lifespan of eight to 10 years, statistically shorter than their American or French cousins, which can usually live to 12.

According to a study published in the journal BioMed Central, it may be impossible to maintain the breed’s current characteristics while improving quality of health. Examining the genes of roughly 100 English bulldogs living in the US, the team discovered that 93% of the 44 male dogs all descended from just male. When it came to the females, 90% of them were genetic descendants of just three bitches.

The research team concluded that this remarkable lack of genetic diversity and high interrelatedness was the result of “artificial genetic bottlenecks,” which means that nurture and not nature has influenced too heavily the breed. The result is that the average bulldog puppy in 2016 is “genetically equivalent to offspring of full sibling parents that came from a highly inbred subpopulation.”

As such, as members of a population with such stymied genetic diversity, breeders seeking English bulldogs with healthier traits have extremely limited options. Breeders have made the decision to start crossing the English bulldog with other varieties in the hope that it will relieve some of the health problems plaguing the breed. If successful, in the future, the English bulldog may look different to what we expect of the breed today, but the dogs will live longer and healthier lives.

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