I do adore PZ Myers, and I mostly agree with what he has to say. But every once in a while, he gets it wrong (like his post on Halal slaughterhouses abroad and somehow linked them to slaughterhouses here in the U.S., that operate in entirely different and much more humane ways). He occasionally jumps the gun before using his skepticism properly.
Sure enough, he's done it again; this time with purebred dogs. His initial point is true: inbreeding is bad. If you do not introduce new genetics into a bloodline, severe deformities will arise. This has led to certain diseases being common in breed lines. Large breeds tend to have hip and back problems. Brachycephalic dogs (such as pugs, English bulldogs, and Pekingese, and so on) often have breathing issues due to problems with soft pallets. These are known and acknowledged problems in the show-dog world. A great deal of reputable breeders here in the States are actively involved with dog genetics and are on the cutting edge of canine medicine.
PZ, you got it wrong. That "documentary" is full of downright wrong information. For example, the documentary attempts to show the "dangerous" progression of some breeds to extremes. They do this by showing an old painting of a Dachshund next to a modern show dog, saying that the dog's legs have been bred shorter, to the point of causing pain for the dog. There are two problems I have with this: The first being that you can still find purebred dachshunds today with the proportions shown in the old painting (also, painters get proportions wrong all the time, so it is not a very accurate depiction of the dog). Some dogs have shorter legs, and some have longer legs. There are longer legged dogs that are show dogs. To say that all dachshunds look like the dog they show as the "modern" dog, and none look like the "older" dog is ridiculous. The second problem I have is the way in which the mention the breed's propensity for back problems makes it sound like any and all purebred Dachshunds will have back problems, which is not true. The breed is know to have back issues, so many breeders will not breed dogs that they know have back problems because doing so would weaken not just their own bloodline, but the breed as a whole.
Another example they use is the Bull Terrier (you may know them as the Target dog, or Spuds McKenzie, or General Patton's dog, Willie). This I have a problem with, as I own a Bull Terrier and have done extensive research on the breed over the years. The documentary shows a dog they claim to be a primitive Bull Terrier, and (again) a "modern" version of the dog. The major problem that was a red flag to me here was the image they chose of the "old" Bull Terrier. The dog they chose is not a Bull Terrier. It is an entirely different dog called an English White Terrier, which was one of the foundation breeds of the Bull Terrier and several other modern terriers, but is now extinct. The Bull Terrier as we know it has been bred with many other dogs and over time developed a unique, egg-shaped head. The only detriment this has for the dog, is that it has made their eyes smaller over time, reducing their vision.
If the people making this documentary can't even take the five minutes of research it takes to discover they are calling two entirely separate breeds the same damn dog, there is something wrong. They also make a completely outrageous claim that the Rhodesian Ridgeback's famous ridge is a result of Spina bifida. Seriously? Are they fucking insane? The ridge of the Rhodesian Ridgeback is essentially a cowlick; it is caused by the hair on the dog's back growing the opposite direction of the rest of the dog's coat. That's it. Genetic diseases the dogs are known for are thyroid conditions, dermoid sinus and hip dysplasia (a common ailment among larger breeds).
The list goes on. PZ even goes so far as to claim that dog shows are on the same level as puppy mills in regards to animal abuse. This is ludicrous. Puppy Mills are horrendous, awful institutions that are based around the systemic confinement of their dogs and over-breeding in squalid conditions, with no concern whatsoever for the animals. Puppy mills are terrible. The breeders and handlers in dog shows go to extreme lengths to ensure the wellbeing of their animals. These dogs have the best care possible, the best diets, well-exercised, and pampered throughout their show careers and onward. That genetic issues have come up is recognized and being dealt within the AKC and UKC associations. That The Kennel Club of Britain chooses to ignore these issues or chooses not to discipline or revoke the licenses of breeders that do not follow their strict health and genetic screening standards prior to breeding or showing an animal is an entirely separate issue. To accuse those that have the most to lose in genetic dog diseases of not caring is ludicrous.
Breeds are not universally recognized. There are differences in the standards, recognized breeds, and breeder oversight practiced by the KC, AKC, and UKC. Some breeds and dogs can not be shown across association due to these differences. That someone would take the problems in management from one association and apply it to all of them is a stretch at the least.
Are there bad breeders? Yes. Do certain purebred dog breeds have predispositions for certain diseases? Yes. However, these two facts do not mean that all of the show dog world is apathetic to the plight of their dogs after decades of unregulated breeding practices. It especially does not mean that problems that exist in the show dog world in England exist here in the United States. Don't get me wrong, I do not think that the dog show world is perfect- it has a lot of problems. I for one prefer to adopt my animals than buy from a breeder, as there are more than enough pure and mixed breed dogs out there that need loving homes.
I own a purebred Bull Terrier, who has AKC papers and comes from a show line. She was sold to us even though her head was not to conformation, and could never be shown. But she has been a loving family companion over the years. We also have a mutt, a shepherd/lab/pit bull mix that found us (she showed up in our front yard one summer morning) that we adopted and love and care for just as much as our Bully. To apply bad logic, and say that somehow an inherent abuse has been applied through the breeding of one of my dogs just because she is purebred, but not the other because she is a mutt, is ridiculous. Blanket statements based on bad information can lead to bad lines of logic, as PZ has shown.