by Dale Malony

Jan. 15, 2004

The pet care industry is growing faster than the rest of the economy and is expected to become a $36 billion market by 2007. Pet health insurance was almost unheard of even 5 years ago, but is rapidly becoming common. Not only is our population pampering their pets to a degree never before seen, their expectations are higher and they want to hold breeders accountable. Responsible breeders are compelled to draft lengthy contracts and the market expects them to "guarantee" health. There are even laws being drafted in many states to strengthen the ability of pet owners to hold breeders legally accountable for the health of their pets.

I had the opportunity to discuss such a law with an aid to a congressman working to draft such legislation here in Ohio. The aid I spoke with was leading the project to draft this proposed law, and her stories which compelled this effort were certainly worthy of attention. I would be preaching to the choir to attempt to inform the readers of Bloodlines that there are many very irresponsible people (unworthy to be called breeders) who knowingly breed unhealthy animals. They talk a good enough talk to sell the puppies they produce, even offering health guarantees, but they go into stealth mode once cash is in hand.

Granted, there is a problem. But the general public and lawmakers often display very little understanding of the realities of breeding for health. Where puppies from any responsible breeder will have fewer health problems than the stereotypical "Back Yard Breeder," (which is a misnomer, as most serious breeders operate in their backyards) there seems to be a widely held belief by the general public that health problems can be avoided by genetic testing prior to mating.

While there are genetic tests available, (tests for PRA and vWD being most prominent) there are actually very few and they are highly breed specific. Where applicable, they are a good tool which could allow rapid elimination of the specific target disease from a breed. But there are very few tests, and none of them are advertised by their manufacturers as applicable to German Shepherd Dogs, from which White Shepherds were extracted. For lists of available tests and which breeds they are effective for, go to: http://www.Optigen.com and http://www.VetGen.com

Other tests, such as CERF, OFA, and PennHIP, merely indicate whether the specific dog is affected. What the public does not widely understand is that a negative test of the parents does not mean that the puppies will be free of the disease. I was fortunate that I was able to persuade the Ohio congressman’s aid to contact Dr. George Padgett, author of Control of Canine genetic Disease, and thus she was educated about some truths of genetic health. The fact is, even most professional breeders today are gambling with every breeding.

Genetic diversity is a catch phrase goal that is very much discussed these days. The foundation principles are very sound and the overall goal is a good one. Briefly stated, frequent inbreeding without out-crossing or proper selection for health and vigor produces a very homozygous DNA. This means that there will be many identical pairs of genes. Not only does this result in the dog being affected with diseases caused by the recessive genes carried, but inbreeding depression can result.

A breeder seeking maximum genetic diversity may run computer programs to calculate a C.O.I. (Coefficient OF Inbreeding) and seeks the most heterozygous DNA possible by mating dogs as unrelated as possible. Such a dog would be less likely to be affected with a disease that is carried, as a maximum heterozygous gene pool creates maximum randomness of gene distribution. This does not reduce the number of defective genes in the pool, nor does it select against defective genes. It can however, reduce the number of dogs affected with genetic disease by spreading genes around as thinly as possible, and thus minimizing matched gene pairs. Still, without locating the genes that produce genetic disease, every breeding is an attempt to dodge random bullets.

Sires become popular when they win, and especially when they are known to produce winners. It is inevitable. It happens with bitches too, only to a lesser extent. Puppies from a bitch known to produce winners will be in high demand, and they will in turn be bred. Breeders in every breed want winning blood.

Much has been written to discourage the use of popular sires, and the point is valid. Even a healthy winning sire WILL carry multiple defective genes. It is statistically unavoidable. And when that sire is bred widely and often, he has a big impact on the gene pool of the entire breed. I expect every breed has certain sires that show up in a high percentage of pedigrees. Many breeds have experienced rapid increases in specific genetic diseases spread by popular sires.

What are your priorities?

If we really want to improve the health of our dogs, we need to do more than dodge bullets. We need to locate them and select against them to reduce their number. Breeders will either choose to make health a higher priority or they may be forced to later. Bad laws with good intentions are only getting more invasive.

As for myself? I place health as second in importance only to temperament. Especially with our White Shepherds, temperament (instincts, intelligence, senses and the use of them) defines their identity more so than conformation in my mind.

In previous columns here, strategies have been presented describing tracking and selecting against defective genes. Primarily, this has involved a relatively complex and laborious system of calculating probabilities and basing breeding selection based upon minimized risk. The process has intimidated many from calculating the probabilities, and thus it is a primary goal of the White Shepherd Genetics Project to not only collect health data, but to automate the calculation process and educate breeders to use it. I hope leaders of all breed clubs either have in place a similar program, or plan to do so.

Though DNA testing in a laboratory is very limited and can be expensive, there is an overlooked genetic test that can be less costly and is effective on a much broader range of diseases. Where an affordable and reliable battery of DNA tests is years away at best, this test is available to us now.

Test mating is neither discussed nor written about extensively, but it could be a breeder’s greatest tool if put to use. October 10^th at the AWSA National Specialty Show, Dr. George Padgett presented some fascinating results of an extensive analysis of the 1999 White Shepherd Genetic Health Survey data. Please note that this data is more applicable to autosomal recessive diseases than to polygenic. With known polygenic defects such as hip dysplasia, it is more important to study the "frequency" that the disease is produced by a given sire or dam than by whether or not it is produced. Some will produce 1 in 10, while others only 1 in 100. Clearly we want to select breeding stock from the dogs producing polygenic diseases with the least frequency.

ONLY dogs that are widely and often bred will reveal with a high degree of probability the genes that they carry. All breeders need to do to learn the genetic makeup of their dogs is to keep in touch with puppy owners and keep good records of health problems of the dogs throughout their lives. Many of the diseases that breeders want to avoid will appear in the first few years of a dog’s life, thus very much can be learned from a widely bred sire. A sire will effectively have his defective genes mapped by the bitches he is bred to!

And not only will the sire’s genes be mapped, but every dam bred to the sire will be test mated for the defective genes the sire is known to carry. If the dam produces a disease that the sire is known to carry, the dam is thus also a carrier. If the dam doesn’t produce it, the dam is effectively proven clean for those genes.

In his presentation Dr. Padgett focused on 2 widely bred sires and one dam whose pups were widely bred. The results clearly showed where defective genes are located, and also (with a high degree of probability) where they are not. White Shepherds are known to have been affected with 57 different genetic diseases. This is in comparison to 128 genetic diseases known to affect German Shepherd Dogs, from which the White Shepherd has been extracted.

The first example given was of a sire which had been bred to 19 bitches, producing 31 litters and 221 puppies. Through the diligent efforts of his breeder to track the health of the puppies he produced, we know that this sire carried 14 different genetic defects. And because he was so widely bred, we know with great statistical reliability that he did NOT carry the other 43 defective genes known to affect White Shepherds.

We also know that he test mated 19 bitches for 14 genetic traits at the same time. Any bitch that has 8 or more puppies that are not affected with a genetic defect known to be carried by the sire is proven with at least 90% probability to be free of that gene. This information can then be used in selection for future matings.

There is no other way than this, at this time, to obtain this information. There is no other way to locate most defective genes other than to produce puppies that are affected with genetic defects. The ONLY way to actually reduce the number of carriers in the gene pool is to knowledgeably select against defective genes. Seeking genetic diversity cannot do it. Testing can’t do it. Selection based on test mating can.

The first problem that leaps to mind for many when shown this information is that it takes time for many defects to express themselves. Some appear soon after birth. PennHIP radiograph can reliably predict by as early as four months whether a dog will be clean of hip dysplasia. Other genetic defects may not appear until after the parents are retired from breeding.

In the language of genetic health, an "unknown" dog is not one that people haven’t heard of. An unknown dog is one owned by an individual who either withholds/lies about family history and what a dog has produced, or who doesn’t make an effort to keep track of the health of puppies and share the info with other breeders.

The following strategies can enable serious breeders to make effective progress towards reducing the number of carriers of genetic disease in their breed. It requires teamwork. Selfish pride and factions will greatly hinder efforts, but even a small team of cooperative breeders can together make demonstrable improvements in their lines.

Strategy #1 – Breed first to a proven sire or dam. A dog’s productive years are short, especially for the dam, so it is critical to begin mapping genes early by breeding to a known dog. If you already have a good idea of what genes may be present based on family history you can select to test for their presence.

This is controversial though. You would be knowingly mating two dogs with a higher than average degree of risk. The payoff can be greater though. A dog with a 50% probability of carrying a specific gene based on family history could be effectively proven clean of that gene if mated to a known carrier, producing eight or more puppies, and none are affected with the genetic defect in question. It would be important to prevent such questionable puppies from being bred and to place them with guarantee in homes supportive of the project.

Strategy #2 – Obviously very little can be learned by the next season that you plan to breed. Wait until later rather than early litters to keep a pup for the next generation. All the early pups will make great show and performance prospects, but the health jury will be out for a while. Be patient.

Strategy #3 – Hedge your bets. Keep your options open with choice pups from early litters by co-owning them or selling them to trusted customers you can expect to partner with you if time reveals good data.

Strategy #4 – Control which dogs are sold with breeding rights. If you do not limit others from breeding dogs that you are not sure of yet, or if you sell them with rights to individuals you cannot expect to breed for health with you, you may enable someone else to spread a gene you are working hard against.

Strategy #5 – Freeze semen. Time is working against us, but technology is on our side. We may not prove that our super stud is clean of diseases that appear late in life until after he is gone or retired. Semen known to be free of certain genes can be hugely valuable to the breed.

Strategy #6 – Do not breed to unknown dogs. This may be the most critical piece of the puzzle. For whatever reason, some people want to deny reality to themselves, or keep hidden what they know. If you bring in blood to your lines from such a person, you will set your efforts back. There is no aspect of these efforts that is more critical than getting accurate data.

Strategy #7 – Keep in touch with your puppy buyers and strongly encourage them to get as accurate a diagnosis as possible for any problem. This message should be given from day one and on so that they aren’t shocked by your requests when mourning their ill pet.

Learn more at the website for the White Shepherd Genetics Project: www.WSGenetics.org