Speaking here as someone who has owned, worked and (VERY occasionally) bred dogs since he was knee high to a grasshopper:
semi-pro-waster is entirely correct. Sorry. The pedigree dog world was started not much over 100 years ago by Jack Spratt and co. (who went on to found and run Crufts). Jack Spratt was the same gent who 'invented' dry dog food in the form of Ships' Biscuits soaked in beef stock. The 'pure breed' dogs were a fad, and a nice little earner.
The entire sorry episode was nothing to do with lineages or ensuring genetic diversity. I apologise, but that made me laugh out loud. There is more inbreeding in the world of show dogs than anywhere else bar hamsters. Not that proper line breeding is necessarily a bad thing in itself. But where you have show people blindly trying to make dogs conform to an arbitrary written 'standard' of so-called ideal, you're always going to have trouble.
Before this 19th century fashion for expensive 'pure' dogs (read: "We're rich, you're not. Aren't we superior?"), dogs were bred for virtually a single purpose: work. That could have been hunting, guarding, herding, droving or whatever. The dogs that were bred, were those that could work. Natural selection easily ensured that only the healthiest, fittest and (naturally) most physically suited dogs survived to breed.
If it couldn't catch rats and bay badgers, it wasn't bred as a terrier. If it wouldn't drove cows it wasn't bred as a farm dog. Dogs in those days had titles according to their function, not a fanciful made-up name dreamt up by a kennel club. Their form followed the job they were required to do, and it did so naturally. The most suited individuals were, naturally, those with the best physical form to achieve their role.
A prime example is the "British Bulldog". Affable as I'm sure they are, they're a monstrosity perfectly highlighting everything that's wrong with the modern 'pedigree' show dog. Some shrewd soul decided to write down what they THOUGHT a 'bull dog' should look like (and believe me it's a fanciful ideal), and then everyone bred dogs to try to match that written standard. What drivel!
Wrinkles to drain the blood away, squat to approach the bull under his horns... nonesense! There's not a working bulldog today which looks anything like this show bred monstrosity. The things can't even catch their breath, never mind two tonnes of scrub bull! That's just one example in thousands, of what breeding to an imaginary ideal does.
Every working dog man knows, form FOLLOWS function, never the other way around. Working dogs are never the easy answer as pets either. A working dog wants to do just that; work. Please don't try to tell me it's plausible (or indeed humane) to buy a working Collie, or a Spaniel, or a sight hound and lock it up in a little house all day. Such dogs (with working blood and hence instinct) strive to fulfil their role. Where do you think all those "Good Pets Gone Bad" shows come from?
"Oh noes, my spaniel ate my brand new £4,000 kitchen!!" "Oh helpz, my terrier's killed the cat next door and destroyed my Italian leather suite! I don't understandz, I walk him to the newsagents every afternoon!"
Anyone breeding dogs for the sake of looks alone is going to run into trouble. You only need attend a single 'show' to see this. Dogs with extremely poor temperaments, dysplastic hips, and deformed faces (and the resultant breathing problems) walk away with ribbons, and earn thousands in stud fees. This eventually means their defective DNA is passed along.
I had one Dobermann breeder recently tell me that their most beloved show dog (out of four) had to be caged up when their own grandchildren visited. He was so aggressive he literally would attempt to all-out attack the child. "This is because he's a well bred guard breed you see".... WTF?!
I have worked with and trained police dogs, security dogs and all manner of working dogs. Even the UK's (fairly badly trained) police dogs would never be allowed to show child aggression like this. But this show dog conforms to the hype generated by the very breeders perpetuating the scam. And it's hurting not just dogs, but people too.
Depending on circumstances, the best 'breed' for you may easily be a mongrel. One of the best working dogs I ever owned was a mongrel - albeit almost by accident rather than design. A dog is what you make of it; but why begin with defective stock, AND pay 5x over the odds for it?
I've gone on very long now, but this is a subject close to my heart. I see the horror stories all too often I'm afraid. Oh well, I'll make way for the "TLDR" crowd, and the "We have pedigree dogs and they live to 8, and are great" folks.
Cheers.
He wasn't injured.