Monday, March 22, 2010

OFA Hips

I've been meaning to get around to putting up a series of posts on breed appropriate health testing. Since I've been a little lax on my monthly goal of doing one health topic a month, I'm going to use this opportunity to talk about health testing. My focus will obviously be more towards what is recommended for great danes by the Great Dane Club of America, but the general idea is applicable to all breeds.

Breed appropriate health testing is something that I feel incredibly strongly about. It's usually the first thing that you can look at to weed out the back yard breeders (BYB) from the reputable breeders. The kind of health testing that I'm referring to is not the kind where the "breeder" just walks into any ole vet and gets a little certificate saying that the dog is healthy. That little certificate doesn't mean that the dog is guaranteed free of various debilitating diseases such hypothyroidism, dilated cardiomyopathy, or even hip dysplasia. If you have a "breeder" that gives you the excuse that they know their dogs or healthy, they don't feel it's necessary, or that they have one of those flimsy health certificates from their local vet, RUN! These are NOT the type of people that you want to get your puppy from! The kind of reputable breeders that you can depend on for the life of your puppy are those that do breed appropriate health screen through the Orthopedic Foundation for Animals (OFA) and the Canine Eye Registration Foundation (CERF). And I will also encourage you to double check any of the registry numbers that you are given to ensure that the number you are given matches up with the dog that it's supposed to be for. It is not beyond a BYB to use one number for all of their dogs because they know knowledgeable puppy buyers will be looking for this kind of information.

For the great dane, there are four recommended health clearances that each dog or bitch pass in order to be considered a viable part of a breeding program. These health tests includes the OFA test for hip dysplasia, the OFA test for the thyroid, the OFA cardiac test, and the CERF eye test. I don't want to go into the details of all four of these tests in this one post. I'm going to stretch it out over the next few months and focus on one test each month so that I can go more in depth.

This month I want to focus on the OFA hip exam. I feel very strongly that everyone be as informed as possible on the various health tests so that they don't make the mistake of buying a puppy from a back yard breeder. If you honestly feel that health testing isn't important in your next dog, then I STRONGLY encourage you to get a dog through rescue. Please do NOT put any money into the pocket of a BYB. This money is only encouragement for them to keep pumping out either unhealthy puppies or puppies who are pretty close to abomination of their respective breeds.

I am able to write these posts from a position of having gone through the various health tests with at least Bess. She has her CHIC certification, which signifies that she has completed all the recommended health testing by her breed's parent club. I also intend to have all of this health testing done on Heffner even though he is neutered and will never be part of a breeding program. I think it is very useful information for those doing pedigree research, regardless of whether the dog is a pet or show quality dog.

Specifically, the OFA hip x-rays are done to determine whether or not the dog in question is dysplastic. Hip dysplasia IS a genetically linked malady. It is also a potentially very debilitating "disease." However, not every dog who has hip dysplasia will outwardly show the signs of being afflicted. This is also something that you can't just walk into any vets office and have them watch your dog walk to tell you whether or not they're dysplastic. This is something that needs to be diagnosed by specific radiologists who are trained by the OFA to read the x-rays and grade them. It's also not a quick and simple process. The OFA has gone through great pains to make sure that they are the gold standard for diagnosing and rating the degree of hip dysplasia in a dog.

The first step is to take your dog to a veterinarian who is certified by the OFA to even do the x-rays. This is important because the dog must be laid out in a specific way, in a specific position, in order to get a viable x-ray. This position happens to be laid out on their backs with hind feet extended behind them. This is a position that a lot of dogs will not willingly go into for a perfect stranger without at least a light sedation. However, it can be done without. This is another reason why there's no excuse for people not to x-ray their breeding stock. Bess' x-rays were taken without sedation at all. Granted she's a very easy going girl, but she was still a bit leery about the whole procedure. The cost of the procedure will vary depending on where you go to have it done. There are now many mobile vets who are equipped to do this who travel to shows. The x-rays can be done there for less than many other places. The veterinarian that I took Bess to is up in Washington state and had a special rate going at the time of $70 for doing both OFA hips AND elbows! That was without sedation. That's a REALLY good deal!! I'm shooting for getting Heffner's hips done next month by the same vet.

Once the x-rays have been taken, they are sent to the OFA where the films are first screened for quality. Along with the x-rays, you send a $40 check to the OFA for assessing and registering the results. If the quality isn't up to par, you are sent a letter or email requesting another set of films. Once the films pass the quality test, they are then reviewed by three randomly selected, OFA certified radiologists. These radiologists then give the hips a rating from 1 to 6 on the degree of hip dysplasia. The ratings are: 1) excellent, 2) good, 3) fair, 4) borderline, 5) mild, 6) moderate, and 7) severe.
The OFA defines Excellent hips as having "superior conformation in comparison to animals of the same age and breed." It has a "deep seated ball fitting tightly into a well formed socket." I am also very happy to say that this is the rating that Bess got on her hips!! Obviously this is the most ideal rating and what you'd be more likely to look for if you're hoping for a performance dog.
Hips that receive a Good rating by the OFA are defined as "slightly less than superior but a well formed congruent hip joint." With a Good hip joint the "ball fits well in the socket with good coverage."

A Fair rating by the OFA is defined where minor irregularities in the hip joint exist. The ball may also slightly slip out of the socket.

A Borderline rated hip is when the radiologists cannot agree as to whether the hip fits into the dysplastic or normal category. With this rating it's usually recommended that the animal be x-rayed again in six months.

A Mild hip is defined by the OFA as having "significant subluxation present where the ball is partially out of the socket causing an incongruent increased joint space." With this type of hip, the socket is usually pretty shallow and the ball isn't very well covered.

With Moderate hips, there is usually "significant subluxation present where the ball is barely seated into a shallow socket causing joint incongruency." Along with this malformation of the hip joint there are usually secondary arthritic changes in the bone. Once the arthritis sets in, it will only continue to progress.
The Severe rating is obviously the worst. And just by looking at the picture in comparison to the others you can see why. "There is significant subluxation present where the ball is partly or completely out of a shallow socket."

Thankfully hip dysplasia really isn't that common in danes any more. This is due in large part to reputable breeders screening their breeding stock and breeding away from this genetic disease. This is a disease that is all to easily avoided and it's a real shame when any animal gets diagnosed with this.

1 comment:

M.T. said...

Wow, very informative post!! Thanks for going to the trouble to write about this subject in detail and sharing it :)