Let’s have an honest discussion about Hip Dysplasia in Labradors
I recently was visiting a Labrador Forum where yet another Lab from OFA tested parents had just been diagnosed with dysplasia. Nestled in amongst all the replies from forum members expressing their condolences was one post that jumped out at me.
“Why are so many Labradors STILL being diagnosed with hip dysplasia even though their parents were OFA certified?”
That is a really good question and I began thinking about creating this very page on my website because of how good a question it was.
Over on another thread I saw this:
"I would NEVER buy a puppy whose Sire or Dam had a fair result from the OFA on their hips!"
and then this:
"MY breeder gave me a warranty on my puppy's hips and elbows and I will get my money back if my dog gets dysplasia".
Before our Angus was diagnosed with dysplasia, I might have said the same. I know for sure that I THOUGHT the same. After all, I had chosen a breeder whose Bitch was certified “Excellent” on her Hips who had chosen a Stud who was also “Excellent”. And Angus’ breeder gave me a health warranty good for two years on Angus’ own hips. I had done everything possible to ensure that I didn’t have a Labrador who would suffer from HD. Right?
The answer is no. The honest answer anyway.
It is the honest answer because there is currently NO genetic test that can be given to ensure that two Labradors will not ever produce a puppy that will develop dysplasia. Despite decades of searching for a "gene" that would identify which dogs will get dysplasia, one has not been found, nor has any combination of genes been deemed as responsible. So breeders rely on subjective readings of x-rays and certification of those x-rays to determine which dogs might increase the odds that puppies will NOT develop dysplasia. Twenty-two years ago, Breeders were asked to be patient and allow several generations of selective breeding to eliminate canine dysplasia, we are still waiting. Journal of the American Veterinary Medical Association 210(10):1474-9 · May 1997
No is also the honest answer because I did not provide the proper environment for Angus. I over fed him and over exercised him. I allowed him to play on stairs, jump as often as he wanted, allowed unsupervised play with older dogs with more aggressive play styles. I allowed the OFA certification of his parents and a breeder's health warranty to give me a false sense of security. Although his breeder honored the Hip warranty and refunded our purchase price, that was little consolation to me as I watched Angus struggle while we found the tools to manage his pain.
The heartbreak of Angus' diagnosis at 10 months of age with mild dysplasia in one hip, moderate in the other, and elbow dysplasia at 18 months sent me researching to help prevent this happening to any other dog I brought home or sent home to another family. I rather quickly found that the trust placed in those OFA certifications and Hip and Elbow Warrantees had led other owners of Labradors to experience that same heartbreak and guilt.
Before we go any further, let’s explain OFA ratings
NORMAL Hips are rated as Excellent, Good, or Fair but ALL are considered normal. The variance is in changes to the joint. The OFA reports that 19% of over 270,000 OFA tested Labradors are ranked as Excellent. (OFA doesn’t report the percentage of Good and Fair ratings although the dogs are given a certification number.)
Borderline Hips means the dog does NOT have dysplasia but has changes that indicate that it may develop later onset dysplasia / arthritis. (Again, OFA doesn’t report the percentage of dogs that receive this rating.)
Dysplastic Hips are rated as Mild, Moderate, or Severe. The OFA reports that 12% of over 270,000 OFA tested Labradors are “dysplastic”. (Again, it doesn’t report the percentage of mild, moderate, severe or even bilateral or unilateral results.) 12%!
Note: The percentages given above (19% / 12%) are found on the OFA Trend Report for Labradors; it is interesting to me that we are never given percentages for "good", "fair" or "borderline" in these trend reports. 67% of the Labradors tested will have been certified within one of those results, yet we are not given the percentages. Would those percentages show us that "borderline" is the natural state of a genetically predisposed large breed dog and that it is ENVIRONMENT that determines hip and elbow health far more often than inheritance?
So, now let's look at how the OFA goes about certifying breeding dogs; there are two levels of testing performed. A preliminary (primarily done to determine if a dog will certify as normal to re-home as a companion if the dog fails OR to breed a bitch at the heat nearest her second birthday) and final certification at two years of age.
Preliminary (before the age of two years) X-ray of hips is read by only one radiologist, while those done for certification after age two is read by three. Final certification is determined by the following (from the OFA website):
Once each of the radiologists classifies the hip into one of the 7 phenotypes above, the final hip grade is decided by a consensus of the 3 independent outside evaluations. Examples would be:
As is easily seen, the process is subjective:
It is important to note that the majority of dogs certified by the OFA are owned by breeders and not by the non-breeding public. This means that the majority of dogs tested are the offspring of dogs who were themselves tested prior to breeding. The x-rays of most Labradors diagnosed with a degree of dysplasia will never be sent to the OFA for certification.
Also of import is the fact that breeders often have preliminary x-rays done before the age at which the OFA will “certify” results and choose not to x-ray at 24 months any dog that received a low normal rating (fair), a borderline rating (no evidence of dysplasia but with “changes”) or a dysplastic rating. Breeders are also unlikely to submit any x-ray at any age, which clearly shows dysplasia to the OFA for certification. After all, the process costs hundreds of dollars, why spend that money for a dog that will not be in your breeding program? And few buyers/owners of companion pets will take the extra step of sending off the X-rays done by their Vet or an orthopedic Vet to the OFA not to mention that companion dogs who never limp or go lame will never be X-rayed for dysplasia.
Logic should lead one to understand then that the actual percentage of dysplastic Labradors produced by certified “Normal” Labradors is higher than 12%.