Breeding of purebred dogs is part art form, part science. The tools of science are used to help select breeding pairs based on health status. The breeder’s experience and expertise are used to interpret the breed standard, assess the structure and temperament of breeding prospects and make a selection based on the type of dog each breeder hopes to produce.

The following tests are available to determine the health status of individual dogs being considered for breeding. Links to additional information on these tests can be found at the end of this article.

Hips/Elbows — OFA (Orthopedic Foundation for Animals) and a number of other agencies offer a certification program and/or evaluation of hip and elbow status. OFA gives permanent certification at two years (or later) with preliminary evaluation available at earlier ages. Other agencies have a variety of different criteria. Evaluation is based on x-rays that can be taken with or without sedation (depending on the dog). Positioning is critical so an experienced veterinarian should be selected to take the x-rays.

Patella/Heart— OFA offers certification at one year or later for patella normal and heart normal status. Most veterinarians can perform these simple examinations (no x-rays or lab tests required). The heart certification has three designations based on the qualifications of the examining veterinarian.

Thyroid — OFA provides certificates for normal thyroid function based on specific parameters tested on a blood draw that is processed through labs that have met OFA’s qualification guidelines (Michigan State, Cornell, etc.—there are currently five in the U.S. and one in Canada). Michigan State also provides a full thyroid panel (eight different tests) which gives a broader picture of thyroid function. OFA recommends rechecks at 2, 3, 4, 6 and 8 years.

Eyes — CERF (Canine Eye Registration Foundation) provides certificates based on an examination by an ACVO (American College of Veterinary Ophthalmologists) member. Eye exams can be done as early as eight weeks. Annual rechecks are recommended. CERF certification is good for one year.

PRA — Newly available (June 2, 2001) is a DNA test to determine whether or not an individual dog has the dominant PRA (Progressive Retinal Atrophy) gene. This test requires a blood draw¹ submitted to OptiGen.

vonWillebrands — This is a bleeding disorder similar to hemophilia in humans which may be detected by a test using a blood draw¹ that can be processed by many different labs (Antech, IDEXX, Cornell, etc.). This test can be performed at any age and is a one-time test.

Cystinuria — This is a urine collection test processed by the University of Pennsylvania and can be done at any age. It is normally a one-time test, but some individuals tested more often have shown that the results can change.

So, you select your breeding pair based on your interpretation of the breed standard. They exemplify the type you wish to produce, complement each other in structure and their temperament and intelligence are what you want to perpetuate. You run all the health tests on both and receive clear results in all areas. You are ready to breed with the expectation that you will produce pups that will be destined to make a positive contribution to the breed.

Not necessarily so. Why? Because we also have to factor in our old friend genetics, the results may not be what we anticipate. And, in some cases, much less than we hoped. The following is a true story, the names have been changed to protect the innocent.

The heroine of this story (Harriet) has matured into a nice looking bitch and has had the requisite testing available (Cystinuria was not a known problem at the time of this story and the PRA test had not yet been developed) passing with flying colors. A suitable partner (Ozzie) has been found who complements her structure and temperament and all testing is clear for him as well.

Twelve bouncing babies were born of this union and grew up as puppies do. Eyes were CERF checked at eight weeks and all were normal-normal² except one who had focal folds. The puppies were aptitude tested at seven weeks and appropriate homes chosen based on the test’s predictors of temperament, two staying with the breeder as show/breeding prospects. As time passed, all the puppies grew and flourished.

At their one-year birthday the breeder contacted all the owners requesting the required patella and heart checks and prelim hip/elbow x-rays be done (this breeder’s contract requires that all pups, regardless of quality, be fully tested by their new owners). Considering the number of pups in the litter, the response was reasonable—65% or eight of twelve. However, the results of the testing were disappointing to say the least.

Heart and patella checks were good, all passing results. The elbows were also good, only one non-passing. The hip results were another story—two good, one fair and five dysplastic. At two years, permanent x-rays were done on four of the eight. Only one passed with a score of good (this is one of those who prelimed good but had elbow dysplasia). The others were either mild or moderately dysplastic. The second good prelim did not have permanent x-rays as the family moved out of the country.

Of these eight dogs, two had autoimmune thyroiditis. Detection of this required a full thyroid panel (not just the more common total T4 that vets often do to check thyroid function). These two dogs (both bitches) had sufficient T4 production, but the T4 was not being converted to T3, something that would not have been detected without the full panel.

In addition, this litter produced three dogs who required ruptured anterior cruciate ligament (RACL) surgery of both legs (one of these has also required a double laminectomy); one needing RACL surgery on a single leg; and, one who is having trouble with a rear leg that the vet feels is ACL related. All dogs undergoing surgery were bitches.

So, why all these problems? Ozzie and Harriet both tested clear, right? We did everything we could to ensure healthy pups would be produced. So what went wrong? Of course we could blame these problems on the sire, on the dam or on sunspots if we want. But, what we have is a case of not having enough information. True, we tested the sire and dam, 

but that just isn’t enough.

To have a better idea of what each dog may contribute genetically to its offspring, we need much more information on the breadth and depth of the pedigree. We need test results on all siblings of the sire and dam and of their sires and dams. In short, we need test results on every dog we can get our hands on that is related to our breeding pair. Only then will we have the information we need to make an informed breeding decision. And, even with all this additional information, there are no guarantees that problems will not arise.

In the true story above, while there was quite a bit of information available on Ozzie, Harriet’s background information was very sketchy. Her breeder guaranteed for hips and eyes, x-rayed hips on the studs and some of the bitches and had eyes checked by the regular veterinarian when they were pups. However, hip x-rays were not submitted to OFA for evaluation and an ACVO ophthalmologist was not used to check the eyes. Thus, it is impossible to check on these clearances at any future date or have an evaluation that is standardized with others within the various certifying agencies.

Unfortunately, this was the case for the majority of breedings being done at that time. Although there has been noticeable improvement to date, this type of situation is still quite prevalent. Breeders may test breeding pairs, but sometimes only minimally. Occasionally breeders will request that show/breeding quality pups be tested. More often a wait and see attitude is taken, finding out about problems only if they are severe enough for an owner to seek veterinary assistance.

While it may be unrealistic to expect that all breeders will test for all things and require that all puppies from each litter have these same tests, this is the ideal situation. If only a few will do this and educate/mentor others to do so as well, it will go a long way toward helping our dogs live longer, more comfortable lives.

In the true story above, Harriet also had a very hard time carrying this litter. She was uncomfortable for the entire time and her hocks swelled to twice normal size. For this reason alone, it was decided not to breed her again and she was spayed shortly after the litter was weaned. Because of the subsequent problems encountered, all females from this litter have been spayed and none of the males will be bred.

For those breeders who are only interested in monetary gain, it is the buyer who must exert their influence by not considering them as a potential source. The law of supply and demand will then work its magic and show these breeders that producing puppies from tested parents is the only way they will continue to sell their puppies. If the breeder you contact is not testing, move on. There will be others that do and while it might take a little more time, the puppy you end up with will have a much better chance for a long, healthy and comfortable life.

For the serious and responsible breeder, the logic of working from a broader information base should be apparent. By doing this you not only reduce the risk of producing puppies that will have problems, help the breed as a whole to reduce genetic disease, but you reduce your exposure on whatever guarantees you have in your contracts.

I would also like to encourage you to take advantage of the open registry systems. OFA is now offering a selection on the submission forms whereby you may elect to have non-passing information available to the public. (You can see how this information will appear by going to the OFA site for online search and typing in Crestwood Big Gun, male, mastiff, between January, 1996 and present). If you have had animals in the past with non-passing information, you may fill out a form to have that information added to their public database (this was done on the link mentioned above, although it did take approximately eight months for the information to appear).

Another registry is GDC which is all open, without having to make a specific election.

Health Testing Links

OFA — Orthopedic Foundation for Animals

CERF — Canine Eye Registration Foundation

GDC — Institute for Genetic Disease Control

OptiGen — OptiGen®, LLC

Michigan State — Michigan State University

                                Animal Health Diagnostic

                                Lab, Endocrinology

MCOA Cystinuria page

MCOA PRA page