Is It True That Mutts Are More Healthy Than Purely Bred Dogs?

No.

But those that survive puppy-hood often are.

Pure-breds tend to get more veterinary attention paid for than do mutts. In other words, the untreated mutts either survive or they die, whereas sickly pure-breds are usually helped to survive. And so the mutts that are still around at 2 years old fluked inheriting genes that made them very hardy, whereas some of the pure-breds still alive at 2 years old ought to be dead.

I wish it were as simple as [Meaghan] thinks. She needs to study genetics to see how recessives and polygenic factors behave. As an example: 2 parents with perfect hips can, when mated, produce several pups that will be severely dysplastic before they reach old age.

The essential differences between mutts and pure-breds are:

(1) Predictability - being consistent for various physical & behavioural features is the whole purpose of having pure-breds, whereas what mutts inherit is very very very much random chance.

(2) Hybrid vigour sort-of applies to mutts. To get true hybrid vigour, you have to cross actual species (as in donkey + horse = mule), but crosses between different breeds or strains do gain some of that effect, especially the increased size and faster growth rate, so it is usually used to produce a slaughter generation. Not many of us use our dogs for meat, though.

(3) A healthy immune system has a great variety of genes to draw on for its purposes. In case you didn't know, apart from what's NOT on the X-chromosome, every living thing has 2 copies of each of its genes; the 2 copies might be the same allele, they might be 2 different alleles (just as 2 wheels for the same vehicle might have the same tread, or might have different treads). Cross-breeds automatically have many of their gene pairs different (which is why it is almost impossible to predict what a mutt will grow up like), whereas the intense line-breeding attempted by some breeders aims to have most of the gene pairs being "identical twins" - the arrival of allergies is a warning that they have done so too intensely. For a healthy immune system it is advisable to have no more than 1 common ancestor in the first 4 or 5 generations, and for that ancestor to have lived to a ripe old age.

And, most importantly:

(4) Breeder responsibility. Few owners of mutts check anything except that the pair are available (and many mutts are produced without the humans being aware of the mating until the bit.ch swells up weeks later!). Whereas a high proportion of breeders of pure-breds check everything relevant to the genetic background of both their bit.ch and the stud they are thinking of using.

It boils down to "pure-bred" not being automatically either a benefit or a curse - what counts is the knowledge & pre-mating checking & research by the breeder. Anyone with a KC-regd bit.ch can let her be mated by a KC-regd stud, but not everyone knows what good & bad features are waiting in the gene combinations the pair supply. Don't expect pet shop pups and puppy-mill pups and pups from ignorant BYBs to be low-risk for genetic problems, regardless of whether they are "pure-bred" or "mutts".

Many people who operate at the bottom of "the dog market" are convinced that GSDs are riddled with hip dysplasia. But my last litter with a dysplastic in it was born in 1983 (and it wasn't planned by _me_ - a pup was allowed to run with his mother because he was too small to reach her target, and anyway he was too young to be fertile - yeah, right.....) The problem being due to several recessives, I could get caught in my next litter, but I keep the odds on my side, not in favour of HD (and as of 1986 my country has a better HD scheme than NAmericans use).

Les P, owner of GSD_Friendly: http://pets.groups.yahoo.com/group/GSD_Friendly

"In GSDs" as of 1967

For both pure bred and mutts, it's on a dog by dog basis. Essentially, it's a myth, but the myth does not come out of no where, and there is some truth in it.

Some mutts can have just as bad genetics as a pure breds, but if a mutt has variable enough genes, he is far less likely to inherit genetic diseases. Pure breds can be bred to avoid genetic diseases, but unfortunately many breeders bred for appearance and not health, thus furthering the problem. And you can't get away from the problem that a genetic bottleneck, like the one created by pure breeding dogs, is never a good idea for a species as a whole.

So if you're asking, if I randomly pick a mutt and pure bred, who will be healthier, the answer is either could be. But if you're asking is the practice fo restricting the gene pool good for future and current genetic health, the answer is a definitive no.

It's also important, when asking about health, to keep in mind all the non-genetic diseases.

Not true.

I look at this from a domino effect point of view... how did said "mutt that is supposedly healthier by some claims" come into existence?

Good, responsible and reputable purebred breeders would not sell their dogs to a home where the dog could be bred to create a mixed breed on purpose or on accident. They have spay/neuter contracts on pet quality and can take legal action if I buyer doesn't abide by that contract. These are the breeders who genetically test their dogs to ensure they are NOT passing on genetic issues to a litter. So with this in place for good breeders, it takes their well bred, genetically tested dogs out of the equation for those mutts that got made.

So then where do those mutts parents actually come from if not from breeders that are properly testing their dogs?

Pet shops, puppy mills and backyard breeders, none of which ever test their breeding dogs for genetic disorders because that would cut into their profits too much and why do they care once the puppy is sold any way, cuz then it's not their problem. So we have people who are either deliberately or accidentally breeding mutt dogs from parents that come from unproven and not tested parents.

So tell me how some people can believe that these dogs are healthier? If you put two dogs together that are a genetic mess, they are going to produce more of the same, not improve on anything. Anyone who believes otherwise is a backyard greeder looking to turn a profit from breeding mutts, period.

I agree completely. I am fine with people who had an accident (though easily preventable), and are selling there mixed dogs at $50-100 if they get them vet checked and their shots. That way they insure the dog is not going to a lab or for bait for dog fighting rings. I do however get sick to my stomach when I am out and see someone selling a poo this or a cocklier, and they want $500 and up for them. I like purebred dogs also. I usually go to a shelter right now, but I always have an idea of a few purebreds I would be alright with, and I wait till I find one. I like purebreds, because you can learn about the dogs, size, traits, and other things. You just have no idea what you are getting with a mutt. The designer mutt creators are not interested in anything but a quick buck. I think they breed mutts because they don't have to pay to register them or anything then. You just have to come up with a cute name, and put a large figure on it. These dogs are put down everyday all over the country, because most people make an impulse buy and find later the dog is nothing like they thought it would be, and then they dump it at the shelter out of impulse and the fact they are to lazy to work with their dog. That is just the way I feel.

Not true.

Mixes are just as prone to health problems.. many of them come from untested and unknown parents/bloodlines.. so there's no way of knowing what genetic diseases lurk in their background. If you mix a lab and a golden, the dog can still get the same health problems of a lab AND the health problems of a golden.

There are alot of unhealthy mixes too, but simply because there are people breeding for profit and not doing genetic health tests on a dog.

It has nothing to do with the "limited genepool".. infact many of the long-established purebreds have a wide gene pool to select from.. actually, a mixed breed dog that comes from generations of neighborhood dogs would have a more limited gene pool in its history than some of the more common purebreds.

Its a matter of how you use the gene pool.. if you study the pedigree and do proper genetic testing, you can actually breed AWAY from health problems.

The best chances of getting a healthy dog is to find a reputable breeder who does genetic health tests on her dogs before breeding them.

Some people say that because mutts have such a mixed gene pool and purebreds can be suseptible to common health issues with that breed, that mutts are healthier, and I might have agreed with you last year, but my sisters lab mix who has been pretty healthy for 5 years compared to my Weimaraner who has stomach issues, just developed facial paralysis, first on her left side then it went to her right side, so I'm going to say no, mutts are not necessarily healthier than purebred dogs. At least with purebreds the health defects or issues can be bred out of them and the parents have usually been tested for hereditary problems. whereas with mutts you have no idea the parents health history so who knows what you're getting with them.

With the breeds that I deal with, I can look at their peds and say what faults they may likely have, and also what faults it's possible to have. So how would it be possible that I couldn't breed a healthier dog than the run of the mill mutt? I have personally seen what these dogs throw generation after generation, so it just stands to reason that I would know what dogs/blood lines to steer clear of. You will find the same is true with any reputable breeder out there. Why do you think we go to all the trouble of showing/running our dogs?

No.

It's true that purebred dogs that were badly bred (no health screening to make sure they are free from genetic problems) can have plenty of inherited problems BUT carefully bred dogs avoid health issues.

Random mix breeds are more likely than well bred purebreds to have health issues because their canine parents didn't check to see if they had any inheritable health problems.

The major health issues for dogs occur in many breeds and the genes aren't breed-specific. In other words, a hip dysplasia gene in a labrador matches up just fine with the HD gene in a german shepherd.

PLUS mutts tend to have family trees that are far more likely to have ancestors that weren't screened for health problems because really good breeders who check their dogs make sure the people who get their pups have them neutered. in other words, the well bred dogs don't make more puppies---so the dogs with the best chance to produce randomly bred puppies are not able to make puppies.

No.

Genes are genes -- if they were present in the parents, they will be present in the puppies, regardless of whether or not those parents were the same breed.

A lucky mutt from two genetically healthy parents will likely be healthier than a poorly-bred purebred from a puppy mill, but there is no "magic bullet" that makes mixes healthier. A mix from two genetically unhealthy parents will inherit those problems; a purebred from generations of health-tested ancestors will be healthier.

"Hybrid vigor" does not apply to complex mammals of the same species.

More info:

http://www.westwinddogtraining.com/hybridvigor.pdf

a poorly bred purebred dog will have it's problems, just like a poorly bred mutt.

A pure bred that has a solid background, and a reputable breeder behind it is no less healthy then the "mutts" bred by bybs.

A reputable breeder will weed out any problems,providing a healthy dog, theres no careful breeding done with mutts.