After 100 years of breeding, dogs are looking a little worse for wear.

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In this video, various canines are dissected to explain why extensive breeding has caused them to suffer.

For instance, the bull terrier has changed over the years, developing mental deficiencies, too many teeth and too small a tail.

Here are some other breeds that have been affected by the last century of breeding:

The German shepherd: Used to be a medium sized dog, but now they’re 30 pounds heavier, with a slower gait and barrel chests, all of which cause painful leg problems.

Pug: Now have high blood pressure, curly tails which can cause the dogs to be paralyzed with age, and a tendency to overheat, leading to heart problems and dermatitis in the fold of their skin.

Boxer: Breeders tried to make their faces even more pushed-in now, and as a result, they have a shorter, upturned muzzle, breathing problems and trouble controlling their body temps.

Salukis: Their extremely long legs leave them prone to serious heart defects.

Dachshund: While they used to be proportioned, now they have much longer backs, are prone to disc problems, paralysis and eye problems.

White terrier: They used to be athletic, but are no longer. Also, they are unable to follow instincts.

Bearded collie: Very prone to skin allergies because hair is now too long.

Saint Bernard: Are much larger now, with pushed-in faces and extra skin, leading to eye issues, bleeding and clotting disorders and paralysis. Also: they slobber more.

Basset Hound: Years ago, they didn’t have such short legs or long ears. Now, they have dermatitis, plus eye and spinal problems.

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English Bulldog: This is the most unhealthy breed of dog. With an average lifespan of 6-plus years, they are prone to every disease.

Anna Caplan contributes to Rare Houston and Rare Animals. 
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