A Look At The Shocking “Improvement” In Purebreds Over The Last 100 Years

Purebreds are cultivated through the process of selective breeding, a process that often comes under many heated debates. This isn’t to say that purebreeding can’t be done responsibly, however if breeders practice inbreeding there can be many health issues as a result.  With a focus on aesthetics many problems get overlooked, in fact many of the more ‘aesthetically pleasing’ characteristics are the very characteristics that lead to such health issues.

For instance, if you take the brachycephalic dog breeds such as bulldogs, pugs and French bulldogs; their snouts have deteriorated over time to develop much flatter faces giving them the appearance of a ‘squished in’ face. Just take a look at these skulls below demonstrating the shocking change of the British Bulldog’s skull over the last 50 years:

source

This dramatic change causes problems such as:

• Breathing difficulty from the overcrowding of tissues in the nasal cavities
• Constant eye infections due to their flattened skulls (shallow eye sockets meaning protruding and exposed eyeballs)
• Skin infections from the excess skin creating deep crevices where bacteria can manifest
• As well as poor ability to tolerate heat

An interesting article by Caen Elegans, ‘100 Years of Breed “Improvement“‘ looks at the development of purebreds over the last 100 years, comparing before and after photographs. Here was the result:

The dogs on the left are from the 1915 book, ‘Breeds of All Nations‘ by W.E. Mason. The examples on the right are modern examples from multiple sources.

It seems incredible that at one time the Bull Terrier was a handsome, athletic dog. Somewhere along its journey to a mutated skull and thick abdomen the bull terrier also picked up a number of other maladies like supernumerary teeth and compulsive tail-chasing.

The German Shepherd Dog is also a breed that is routinely mentioned when people talk about ruined breeds; maybe because they used to be awesome. In Dogs of All Nations, the GSD is described as a medium-sized dog (25 kg /55 lb), this is a far cry from the angulated, barrel-chested, sloping back, ataxic, 85-pounders  (38 kg) we are used to seeing in the conformation ring. There was a time when the GSD could clear a 2.5 meter (8.5 ft) wall; that time is long gone.

The Basset Hound has gotten lower, has suffered changes to its rear leg structure, has excessive skin, vertebra problems, droopy eyes prone to entropion and ectropion and excessively large ears.

The English bulldog has come to symbolize all that is wrong with the dog fancy and not without good reason; they suffer from almost every possible disease. A 2004 survey by the Kennel Club found that they die at the median age of 6.25 years (n=180). There really is no such thing as a healthy bulldog. The bulldog’s monstrous proportions make them virtually incapable of mating or birthing without medical intervention.

The Pug is another extreme brachycephalic breed and it has all the problems associated with that trait – high blood pressure, heart problems, low oxygenation, difficulty breathing, tendency to overheat, dentition problems, and skin fold dermatitis. The highly desirable double-curl tail is actually a genetic defect, in more serious forms it leads to paralysis.

Once a noble working dog, the modern St. Bernard has been oversized, had its faced squished in, and bred for abundant skin. You will not see this type of dog working, they can’t handle it as they quickly overheat. The diseases include entropion, ectropion, Stockard’s paralysis, hemophilia, osteosarcoma, aphakia, fibrinogen deficiency.

The Dachshund used to have functional legs and necks that made sense for their size. Backs and necks have gotten longer, chest jutted forward and legs have shrunk to such proportions that there is barely any clearance between the chest and floor. The dachschund has the highest risk of any breed for intervertebral disc disease which can result in paralysis; they are also prone to achondroplastic related pathologies, PRA and problems with their legs.

A shorter face means a host of problems. The modern Boxer not only has a shorter face but the muzzle is slightly upturned. The boxer – like all bracecyphalic dogs – has difficulty controlling its temperature in hot weather, the inability to shed heat places limits on physical performance. It also has one of the highest cancer rates.

As mentioned at the beginning of this article, not all selective breeding is irresponsible, it is simply breeding for aesthetics sake without any regard for the dog’s overall health that is the route of the problem.

Source: Asher L, Diesel G, Summers JF, McGreevy PD, Collins LM. (2009).Inherited defects in pedigree dogs. Part 1: disorders related to breed standards.  Vet J. 2009 Dec;182(3):402-11.