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Are Purebred Dogs Really at Risk?

The response to recent articles about inbreeding, linebreeding and the all-important question of how healthy our purebred dogs really are has been interesting. The first article, “Inbreeding: A Force for Good – or a Skeleton in Our Closet?” resulted in a lot of comments on the website and a couple of emails to me. When the second article, Westminster and Crufts BIS Breeders Speak Out, plus Goldens and Cancer Research appeared, the reaction was almost the reverse: just a few comments on the website but many emails, often with attachments consisting of genetic studies and scientific research, and sometimes asking if we can “talk about this” on the phone. It’s almost as if readers don’t want to debate this in print, and some are obviously afraid of being labeled “animal rights” activists.

Can we discuss that term first for a second? It’s one of the most misused words ever. We are all “animal rights” people, I hope, in the sense that we agree animals have the right to a decent quality of life, edible food, clean water and freedom from pain. What we’re against are the “animal rights extremists,” who in fact in many cases don’t seem to care about the animals at all. It does our cause a lot of harm that we publicly label them as “animal rights” people — which is, of course, a term we should reserve for ourselves.

Never before have purebred dogs been subjected to as much scrutiny as in the past few years. Some of that attention obviously has an ulterior motive of discrediting us, trying to make what we do seem like a suspect, even unethical, activity. Why anyone would initiate such a smear campaign isn’t clear. Who could possibly have anything against the fact that we try to breed the best dogs we can, or that we enjoy getting together to show these dogs to each other, often in front of a more or less befuddled public? It would seem like a pretty harmless activity, right? Of course there are always dog-haters, people who can’t accept the fact that we want to share our lives with four-footed friends — but why single out purebred dogs? The “snob factor” can admittedly be a little difficult to take sometimes, but that really isn’t the main reason we like the dogs we have, is it? We just happen to enjoy the company of certain kinds of dogs that, physically and temperamentally, fit our lifestyle. What’s so bad about that?

It would be a huge mistake to discredit all the attention that’s directed at us, however. A lot of people who love dogs, including purebreds, are concerned about their health and the possibility that perhaps purebred dogs today are not as healthy as they used to be. A major reason for believing this, as far as I can understand, is that the gene pool for any “pure” breed is necessarily limited, and will inevitably be shrinking with each generation, resulting in genetic drift and the doubling up on undesirable characteristics. Over many decades, now over a century in some breeds, what effect will that have?

However, unless reliable comparisons from long ago exist (and they don’t, in any breed that I am aware of), we really can’t know for sure. It’s more a suspicion, based on a general feeling and anecdotal evidence that our dogs need more veterinary care and are affected by more illnesses now than in the past. Could that impression be based on the fact that we all undeniably know more about diseases than we used to? Or that we communicate much better with each other today, via the Internet, so we know a lot more about the dogs we bred (and that others bred, too) than we did years ago? Is the problem a polluted environment that causes certain illnesses, or is it simply that veterinary care has advanced so far that it’s possible to diagnose and treat diseases that in the past nobody would have been aware existed?

“Bliss” was born in April 2002 and is pictured at home in advance of her 11th birthday. Photo courtesy of Shawn Westbrook.

Breeders’ Health Records

These are big questions. I wish breeders’ health records from 25 or 50 years ago still existed, but usually they don’t. Even if they did, how complete and reliable would they be, and would the breeder in question be willing to share them, warts and all? (And not just warts, but serious problems as well.)

Since I myself have, in fact, bred dogs for nearly 50 years, it made sense to take a look back at my own dogs’ health history. They illustrate quite well both what you may find, and what you probably can’t. I kept pretty careful records — or at least what in the past were considered careful records. Some breeders just scribble down an address of a pet puppy’s new owner, and then lose that after a few years (or months), but I bred rather seldom, barely one litter per year on average, so record-keeping wasn’t as laborious for me as it would have been for a bigger breeder.

It took a few hours to pull the data together, dragging out the big binder I used for recording details about the puppies I bred in the past, before switching to a simple Word file on my computer about 20 years ago. The information is not nearly as complete as I wish it were, which is partly my fault (for not following up more diligently), partly inevitable (puppy buyers move away, lose touch or don’t respond to inquiries). There was also the feeling in the past that these details weren’t that important, because health could simply be taken for granted — although I now wonder if we were just ignorant or fooling ourselves. My numbers aren’t large enough to provide a statistically valid source anyway, but for what it’s worth here are some details of what a single (and in this case, small in numbers but long in years) breeder can compile.

Since the first one in 1966, I have bred 43 litters of Whippets. (This does not include a few early litters of Afghan Hounds and Greyhounds, because I have no recent comparative data.) Fifteen of the litters were co-bred with others, which may explain why some records are missing. These litters resulted in 248 puppies that lived beyond the first 24 hours, 137 males and 111 bitches. That’s an average of only 5.7 live puppies per litter, which seems like a rather low number, but varied from just two puppies in a couple of litters to several with 10 or 11 puppies. All of them were successfully reared by their dams (sometimes with a little help from another bitch).

Interestingly, litter size appears to have increased in recent decades. However, there were also 21 puppies — one for nearly every second litter — that were either born dead or culled within the first 24 hours. I’m not sure if that’s more than average; probably not, and that figure has remained stable over all these years. Five of the stillborn puppies were in the three litters that were born by C-section; none of these dams were bred from again. Most bitches were only bred once or twice; three who were particularly good mothers produced three litters each.

Of the puppies that survived the first few weeks, all except two or three grew to adult age, as far as I know. (It’s impossible to be certain, but a puppy buyer who loses his dog within the first year or so would almost certainly notify the breeder, even if he doesn’t stay in touch later.) One was lost during routine surgery under anesthesia at 4 months, and one was killed in traffic. At least 15 of the male puppies were monorchid or cryptorchid; there were probably more, but this would be difficult to confirm unless you stay in touch with the pet owner. That was disappointing for owners who had hoped to show their dogs, of course, but caused no medical problems for the dogs.

“Trixy” was born May 28, 1996 and died late July 2012 at the age of 16. Photo courtesy of Charlotte Laning.

Average Life Span

The average life span of the adults I have information about was 12 years, excluding seven that were killed in accidents, but including a couple that died young of various diseases, as well as several that lived past 15 and even 16 years of age. The average age will most likely increase in the future, as at least a dozen dogs I bred since 1998 are still alive and well at 12 to 14 years of age.

What was interesting to me, studying these records for the first time in years, was a conclusion that I can’t prove but seems pretty clear: on the one hand, more dogs have been affected by various inheritable (or reportedly inheritable) diseases in the last 20 years than in the first 27, while on the other hand contemporary dogs that were not affected lived longer lives than those born earlier. In the 1960s and ‘70s, it was considered normal for a Whippet to die “of old age” by around 10 or 12 years of age; today it’s not unusual for them to live several years longer than that.

It’s difficult to find comparative figures, but I came across records for a mostly unrelated Whippet population in England and Australia from the 1950s and ‘60s. The average life span of these dogs was nearly 9 years. Cause of death is not listed, but this quite possibly includes death by accident, which would of course affect the figure.

I’m not going into detail about the problems that have affected dogs I bred over the past 20 years or so; it’s sufficient to say there were individual cases of diseases I never even knew existed. As they say, “If you breed long enough you’re sooner or later going to come across pretty much everything…” The one problem that was in any way consistent was heart disease, which shortened the lives of a total of five dogs, including most tragically one 18-month-old youngster. We’re talking about a very small percentage, of course; it’s true that a Whippet is more likely to be killed in a traffic accident than by congestive heart failure, but that’s still a frightening figure. Furthermore, I know I’m not the only breeder to have had experiences like those above. This makes sense, of course, since no breeder is an island, and the lines I’ve bred from come from the same foundation as most leading kennels in America. Conscientious Whippet breeders test their dogs, use common sense and keep hoping for the best — but is that the best we can do?

What I wonder, though, is whether these problems were always around, although I was unaware of them. That famous dog, born in 1971, who was put to sleep at 9 and a half “because he kept coughing” — what did he actually die of? There are other cases where I wish I had asked specific questions and demanded clear answers, but like most others in those days I didn’t. That makes the present situation more difficult to assess.

“Taz,” pictured here with his owner, Greg Soyster, celebrated his 15th birthday in 2012. Photo courtesy of Nancy Soyster.

A Limited Gene Pool

An overseas breeder friend puts it well: “Purebred dogs in general share a limited gene pool, and conditions like [those we discussed] are likely to appear in almost all breeds sooner or later. Whippets are no exception, but we are lucky in so far as we have never limited our genes to certain colour patterns and may thus have a healthier genetic makeup than many other breeds. Fifteen years ago I thought it was really bad to produce so many monorchids in the […] litters we bred then. Well, monorchids seem a minor problem [compared] to some other conditions lurking out there!”

So are purebreds finished? Not by a long shot. But a lot of well-educated people are convinced we’re on a slippery road to ruin. I don’t see how anyone can be sure without having access to comparative records from the past, but nevertheless this is a serious subject that every breeder needs to learn more about.

There’s no shortage of genetics experts, scientific papers and websites out there. The problem is most of them are not necessarily easy for mere mortals to understand, without specialized knowledge and education. Writing about them all would require an additional several columns, but I want to mention them anyway as suggested further reading. Here are some references:

You may know her as the brilliant show dog photographer Carol Beuchat, but Carol also has a doctorate and runs a website on molecular genetics that’s worth studying: www.carolbeuchat.com. Quote: “… we’re learning a lot about canine genetics that can be put to good use by dog breeders. Identifying the gene behind a particular trait can now be done using cheek swabs from a few dozen animals in a few months or even weeks. We can begin identifying the genes associated with non-Mendelian and polygenic traits. This is information dog breeders can start using to take some of the guesswork out of breeding, to make better predictions about the qualities in their next litter, and to breed healthier, happier dogs.”

Jo Thompson, Ph.D. penned the article, “How many Founders does it take to make a Breed,” which discusses the minimum number of unrelated founders required to establish a long-term, viable population of any breed. The number, according to this paper, varies from five to 50 depending on the source and species. It was originally published at www.modernbasenji.com.

“Managing the Genetic Health of the Basenji Population,” by Robert C. Lacy, Ph.D., and Beuchat, is a response to the above paper, with focus on the question of how many dogs are required to rescue a breed population at risk for extinction — typically 20. The Basenji is one of very few breeds where a large population of animals from which the founders were originally drawn still exists. Groups of imports from Africa have been incorporated into the AKC Stud Book in recent years, and the AKC Board of Directors has voted to keep the Stud Book open through 2020.

“Genetics Selection Evolution” consists of research into the history and structure of the closed pedigreed population of Icelandic Sheepdogs; go to www.gsejournal.org.

“Population structure and genetic diversity of worldwide Nova Scotia Duck Tolling Retriever and Lancashire Heeler dog populations,” by K. Mäki, is another interesting piece. We don’t have Heelers at AKC shows, and Tollers are still fairly rare, but this is interesting, if heavy, reading. The summary explains that “more than 50 percent of the genetic diversity in the reference populations was explained by two ancestors in the [Tollers] and five in [Heelers].” The author states it’s necessary to use unregistered farm dogs in breeding Heelers, and outcrossing with another breed in Tollers.

“The State of the Irish Wolfhound,” by Pernille Monberg, a Danish breeder and researcher, points out that the average life span in her breed now is around 6.5 years. Interestingly, she mentions the famous Ch. O’Leary, about whom it was written as early as in 1916 that “a large number of O’Leary’s progeny died of heart trouble, as he did also.”

Lorna J. Kennedy, Ph.D., whose paper “DLA Diversity in Dog Breeds” puts the Standard Poodle in focus. Among her conclusions is that almost every Standard Poodle in the world today goes back to the Wycliffe kennel of the 1960s in Canada.

“The Golden Retriever Club of America National Health Survey 1998-1999” is now dated, but still interesting.

Written by

Bo Bengtson has been involved in dogs since the late 1950s and judged since the mid-1970s in Sweden, Norway, Denmark, Finland, Great Britain, France, Germany, Austria, Holland, Italy, USA, Canada, Australia, New Zealand, Mexico, Puerto Rico, Brazil, Japan, China and Russia. He has judged twice at Westminster, twice at Crufts and four times at the FCI World Show, as well as the U.S. national specialties for Scottish Deerhounds, Whippets, Greyhounds and Borzoi.

5 Comments to “Are Purebred Dogs Really at Risk?”

  1. cbeuchat Carol Beuchat, PhD says:

    The reason Lacy and I wrote that article was to REFUTE Thompson’s claim that a dog breed could be founded with only 20 animals (for which she references Lacy as her authority). This is NOT correct, it is not what we said, and I refer you to my discussion of Thompson’s paper on my website, where you can also read an early version of our paper where we explain why Thompson’s assertion is incorrect (I will make a pdf reprint of the paper available there shortly).

    http://www.carolbeuchat.com/2012/05/do-we-really-need-new-basenjis/

    I have also discussed the papers about Lancashire Heelers, Tollers, and Icelandic Sheepdogs referred to in Bo’s essays in previous blog posts on my website.

  2. Bo Bengtson says:

    RESPONSE TO CAROL BEUCHAT:

    This is an exact quote from your article: “”As Thompson [in the other paper referenced] notes, a recommendation of 20 effective founders is typical as the starting point to rescue a population at risk of extinction.”

    I don’t see how it’s possible to interpret that any other way than it’s written. I wish it had been possible to quote in more details from the many scientific papers submitted. Thanks.

    Bo Bengtson

  3. cbeuchat Carol Beuchat, PhD says:

    That is indeed a quote from the beginning of our paper, in which we are repeating a statement made by Thompson in her paper.

    However, for the whole rest of the paper, we go on to explain – at some length – why this statement is NOT appropriate for dog breeds, because populations of dogs are NOT managed in the way that endangered species are. Endangered species are intensively genetically managed to keep loss of genetic diversity to an absolute minimum. This requires that ALL animals are bred, and the genetic contributions of the founder animals to subsequent generations are kept in balance. Under such a management scheme, the population is increased in size until it reaches several hundred individuals, at which point the danger of losing the genetic contributions of a particular founder are minimal because the genes are widely dispersed in the population.

    Dogs, of course, are not bred this way. Breeders make choices independently of each other, so for the most part there is no genetic management at the breed level. Furthermore, they specifically breed to reduce genetic variability as the most efficient route to fixing the genes for the traits preferred in the breed. Line- and inbreeding increase the genetic influence of particular dogs in the breed, and most puppies that are produced are removed (along with their genes, good or bad) from the registered gene pool (sold as pets). The results are precisely the opposite of what is necessary to establish and maintain a population of animals over the long term – genetic diversity declines and inbreed depression increases, as reflected in a decrease in “fitness” – fertility, lifespan, health, resistance to disease.

    Furthermore, because selection requires genetic variability (if everybody is the same, there are no differences to select for), the options for selecting for various traits decline. Genes are not inherited independently – they tend to be passed along in groups (e.g. if they are near each other on the chromosome), and selecting for one particular gene also selects for (or against) all the other genes it is linked with, good or bad. (This is caused Linkage Disequilibrium). Selecting against a particular unpopular color might also select against some feature of temperament; selecting for nice earset might also select for kidney disease if the responsible genes happen to move as a group. It’s as if every day after you’re done cooking supper, you throw out everything in the pantry that you didn’t use. You can make another nice supper the next night (minus the curry and gummy bears), and throw out the unused ingredients. If dinner one evening doesn’t require sugar and that gets thrown out, your options for desserts after that are going to be pretty limited. If there is no other pantry to go to where you can find sugar, there just isn’t going to be sweet stuff on the table after that. The strategy in managing endangered species is to make certain that there is always a supply of every possible ingredient in the pantry, and what gets cooked depends on a menu that will not completely deplete any ingredient.

    Conservation biologists would love to be able to rescue an endangered species by being able to collect 1000 genetically diverse animals from the wild, and have the resources to house and care for them in several different locations to minimize the possibility that a disease outbreak or catastrophe could wipe out the entire species. But of course, frequently there are precious few animals left to save – the California Condor was reduced to 18 animals when all were captured from the wild and placed in a breeding program, from which many have now been reintroduced into the wild), and funds for housing and caring for these animals are rarely adequate. So faced with many limitations, most conservation efforts try to work with the fewest number of animals possible, for which the rule of thumb is about 20. But every breeding is managed, every animal is bred, and the entire gene pool is protected to the highest degree possible.

    Thompson’s article was about Basenjis. Basenjis have been added to the pedigreed population multiple times since the breed’s founding. But there has been no genetic management of the breed as a whole. The genes of newly imported animals were not integrated into the larger breed population, and selection for particular traits was strong from the beginning, with only select offspring being allowed to reproduce themselves. In fact, the animals brought back from Africa were not even representative of the genetic diversity of the free-living populations in the Congo (which have survived without human intervention for thousands of years). Instead, puppies were carefully selected in the field for characteristics most suitable for conformity with the breed standard, then upon arrival in the US, there was further screening to add only the “best” of these to the stud book. Much of the physical variability seen in the free living dogs – in tail carriage, size, ears, and other features – was selected against, along with whatever genes might also be associated with those traits. If the goal is to establish a new population of animals from founders that will be genetically sustainable over the long term, this violates the most basic procedures.

    There is nothing new in the concepts here, either for wild animals or for that matter for dogs. In fact, John Armstrong, a geneticist and poodle breeder, ran a website (The Canine Diversity Project; http://www.dogenes.com/diverse.html) with the single-minded goal of educating breeders about the need to manage the genetics of not just the next litter of puppies, but of the entire breed, which is the pantry that needs to sustain and support the needs of the breed for generations to come. Armstrong’s sudden and untimely death in 2001 robbed the dog fancy of the expertise of an extraordinary man whose wisdom is needed now as never before. His website has been maintained in his absence by breeders (and I believe also a daughter) who understand the importance of this information and is widely referenced by breeders and clubs as a source of reliable information.

    A summary of specific points we make in our paper –

    a) Statements about the minimum number of founding animals needed to build a viable closed population assume that breeding will either be random or will be managed to preserve genetic diversity and minimize inbreeding.

    b) Increases in inbreeding should be kept to less than 1% per generation if possible, and when the population average reaches 5% new animals should be introduced to the population to boost genetic diversity. When cumulative levels of inbreeding reach 10% (equal to a loss of 10% of the genetic diversity of founders), extraordinary efforts are implemented to increase genetic diversity, including introduction of related subspecies (as was done in the case of the Florida Panther).

    c) For purebred dogs, the goal is to produce healthy animals that are good representatives of their breeds and can continue to respond to selection generation after generation. With proper management of genetic resources of the breed as a whole, including strategies to protect a reservoir of genetic diversity and to introduce new genetic variation if necessary, it is possible to breed healthy, happy dogs for generations to come.

  4. Bo Bengtson says:

    Thank you for adding to the conversation. I have suggested that your very interesting comments should be published as a separate article.

  5. Thomas Münch, Germany says:

    Thanks for your very well written article.
    I believe not all is lost but we (i.e. breeders of purebred dogs) must be even more careful when choosing breeding stock.
    I sincerely hope that, over the next couple of years, genetic testing will enable us to more precisely determine a combination of risky genes.
    Meanwhile, let’s all try to do what we think is best and hope for the best.

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