The OFA is the Orthopedic Foundation for Animals, Inc. and is responsible for maintaining the hip and elbow registries, among others, for dogs in North America. At the OFA a panel of three board-certified veterinary radiologists will read your dog’s pelvic radiograph and give the dog a rating of Excellent, Good or Fair hip structure, all of which are permissible to breed. They will also examine your dog’s elbows via standardized XRay procedures, and rate him “Clear” of elbow dysplasia. As many of you are probably aware, the Ontario Veterinary College radiologists will also read hip and elbow XRays amd will grade them “Clear”, but these ratings are not standardized along OFA guidelines, as the OVC will grade hips at 18 months of age (versus 24 months for OFA), and they do not have the grading system(s) of the OFA.
Canine Hip Dysplasia (CHD) is an inherited trait involving multiple gene factors. CHD is a developmental disease, all dogs are apparently born with normal hips, but, in affected individuals, the radiographic signs become evident within several months to years. The OFA reports that the accuracy of diagnosis is approximately 95% at 24 months of ge. Because OFA data is drawn from breeders submitting radiographs that have been pre-screened by their own vets, this data is biased toward normal (i.e. if your vet told you your dog was dysplastic, you would not likely send the XRay into the OFA, so they receive a greater percentage of normals then are actually present in the population). This presents a scary picture in our breed. OFA results from January 1974 to July 1991 show that 37,497 Rottweilers were evaluated and that 23.3% were dysplastic!! …Imagine the numbers who were not sent in because their own vets diagnosed CHD at the time the XRay was taken, in addition to the numbers that were never even radiographed!! I would hazard a guess that probably about 40% of our breed is affected by this crippling disease!!
The OFA suggests that we, as responsible breeders should only breed dogs with normal hips to dogs with normal hips. Prospective breeders and buyers should check OFA numbers with the registry and ask to see the OFA certificate. If an OFA number canot be verified assume the dog to be dysplastic until proven otherwise! Preliminary evaluations can be done as early as 4-5 months of age with 85-90% accuracy. Please remind your vet that when taking the XRay anesthesia is recommended, and for bitches the OFA recommends radiographing 3-4 weeks before or after a heat period to prevent any false positives due to hormonal effects of the estrus cycle. The OFA further states that there are no environmental factors which cause CHD, there is no evidence that vitamin C is beneficial in reducing or preventing CHD, high caloric intake resulting in rapid growth and increased weight gain may exacerbate dysplastic hips, but will not create hip dysplasia, running, jumping, slick floors, etc. will not cause hip dysplasia, and that previous injuries to the legs or hip structure can be recognized on the XRays and are taken into account when evaluating hip status.
The OFA elbow registry is for dogs 24 months of age or greater, and is a standardized evaluation of the elbow joint for ununited anconeal process, fragmented coronoid process, osteochondrosis, or any combination thereof which would constitute elbow dysplasia. Over 70 breeds have been evaluated for elbow dysplasia by the OFA, and positive results have been found in 20 breeds. Rottweilers are currently ranked fifth on the affected breeds list. As of December 31, 1991, 402 Rottweilers have been evaluated, with 38.8% showing signs of elbow dysplasia. Again, these results are biased toward normal, pushing our breed’s actual affected percentage up close to the 50% range!! Certainly something to ponder…whether breeding or buying!
Speaking as a fellow breeder, I cannot disagree with any of the above mentioned ‘scientific’ results, but I will admit to you that I take every precaution possible to prevent CHD and elbow/shoulder problems in my dogs. As well as breeding only unaffected dogs and buying pups only from unaffected parents, I also line my whelping box with indoor/outdoor carpeting and flannel sheets rather then newspaper for better traction, I try not to house dogs on cement any more then is absolutely necessary, I carry puppies up and down stairs for as long as my back can handle it, there are no fat dogs (especially puppies!) at my house (which my handler keeps complaining to me about!), dogs are not allowed to jump into the back of the truck (for example) until after 24 months of age, and no forced exercise is done (i.e. bicycling) until they are certified. I prelim all my dogs at approximately one year of age, if they are not CHD free at that age, I would spay/neuter and place them in a suitable home depending on the severity of the disease. I radiograph the dog’s elbows at 24 months of age and send the radiograph to the OFA for evaluation at the same time as the hips are done.
I shall give approximate costs (from the OVMA Fee Guide for Small Animal Procedures 1993) involved in having a dog radiographed and submitted to the OFA for CHD evaluation.
- Anesthesia & Reversal: $60.00
- Radiograph: $47.80
- One Half Day Hospitalization: $16.90
- Courier to OFA: $30.00
- OFA Evaluation Fee: $25.00 (US Funds).
Many vets have a standard fee for radiographs sent to the OFA which may make this slightly less expensive, but prices will vary. The elbows can be radiographed at the same time, with the additional charge of two XRay films. The OFA charges $15.00 to prelimhips or evaluate elbows and $25.00 to evaluate hips and elbows on one dog submitted at the same time.
“A stitch in time saves nine” and “Penny wise, pound foolish” certainly applies here to breeders who complain that they can’t afford to have their dogs hips and/or elbows XRayed prior to breeding, or that they just get their own vet to read the radiographs because the OFA is too expensive. I, personally, cannot afford the loss of respect in the dog community, the emotional and mental anguish I would suffer by producing dogs with defects that I could have prevented (or at the very least took every precaution available to attempt to prevent), and I cannot afford to replace puppies or refund purchase prices because my dogs are not healthy. PLEASE PEOPLE, MAKE USE OF THESE REGISTRIES PRIOR TO BUYING OR BREEDING, FOR THE BETTERMENT OF THE BREED (afterall, isn’t that what we are all striving toward??)
By Dr. Catherine Priddle, DVM.