Cardigan hip scores: A dose of orthopedic reality (Cardigan OFA, PennHIP, DI, etc.)

Gird your loins, because what I am about to say is (and should be) controversial. The only thing I can say is that I came into this research with a very strong bias toward what I’ve always thought of as the one incontrovertible rule in dog breeding: ALWAYS TEST THE HIPS AND ALWAYS SUBMIT THE TEST. What I will explain below was so striking to me that I find I don’t have anywhere near the same confidence in that unbreakable rule. So don’t dismiss or crucify me before you read and understand it too.

When I was hit with two pelvic “crises” in the same month (Clue’s injury and x-rays, including trying to interpret her eventual breeding soundness, and Bronte’s breeding date being moved up dramatically) I knew I had to get my mind around the hip issue in dwarfed dogs. I wanted to make sure that I was making good decisions and I understood the potential outcomes within various theoretical matings.

I started this in the same way I have always done: a pedigree analysis using OFA and some discreet inquiries to people who have been in the breed a lot longer than I have.

Here’s what I found:

1) There is a very troubling and almost complete lack of consistency in the OFA results for this breed. Ditto for PennHIP. I’m not talking about the fact that too few people are certifying; I mean that there is virtually no predictability in scores based on the pedigrees. I am computer-savvy enough to piece together a lot of information from OFA searches, so I didn’t find myself fatally hampered by the fact that there aren’t as many actual results in the pedigrees; I could always find a brother or a cousin or whatever and usually multiples of both.

What I saw was a situation that looked totally random and inconsistent. Two dogs with good ratings producing, within a single litter, everything from Excellent to Moderate. Stud dog lines that I know to have a moderate to high COI (which should indicate consistency) flipping from good to dysplastic and back again.

It didn’t make any sense. Even when you have a breed that is genuinely in trouble, the dysplasia tends to fall into family lines and at least a few people have consistent success. When you see the bad family lines doubled up on, you get worse hips again. You can get some unexpected stuff, but in general good hips make good hips and bad ones make bad ones. And so on. The OFA picture in Cardigans was one of seemingly random and completely unpredictable results.

2) Hip scores do not correlate anywhere near as well as they should with soundness or comfortable working lives. When I spoke to the orthopedic surgeon about Clue, I got some very good and very candidly given information. He said several things: This is not a breed he sees, as a surgeon who does lots of work to relieve pain in hips or to analyze x-rays. This is not a breed coming in with pain issues. It’s not a breed he associates with dysplasia symptoms with any regularity. He does not recommend OFA for corgis of any type, because he feels that the scoring is more or less guesswork unless the joint is clearly already arthritic or the socket just plain doesn’t exist, and EVEN THEN he rarely sees dogs come in with pain.

He said, and this is close to an exact quote, “These are dogs with weird hips, and they get along just beautifully on those weird hips.”

THIS IS SO IMPORTANT. I cannot make that in caps big enough.

There is a phenomenon called “a disease of numbers.” Good human docs know it well. A disease of numbers is a condition that causes a value on a test or chart to go high or low but may not actually correlate with any bad outcome.

Whenever you’re doing medical research, you have to be aware of this phenomenon and prove beyond a shadow of a doubt that the numbers are actually predictive. So nobody stops with “Your blood pressure is high. That’s bad.” It has to be “Your blood pressure is high. That’s bad because we know FOR SURE that high blood pressure is associated with these ten disorders, with precise and reliable predictive accuracy.”

My point here is that we have not satisfied that burden of proof when it comes to the classic OFA-type evaluation of Cardigan hips. We do not know at what point a hip will or will not cause quality of life issues. We are trying to evaluate them based on how close they are to the hips of a long-legged, short-backed dog (the greyhound–that’s the ideal hip and the one OFA is based on). Think about that: Does our breed look or function ANYTHING like a greyhound? They have entirely different biomechanics and centers of gravity, very different muscle formation, completely different cartilage, ligaments of a different shape and strength. What proof is there that making their hips more like a greyhound’s actually improves quality of life?

Conversely, what proof is there that looser or shallower hips mean a poorer quality of life FOR THIS BREED?

I would also add that we do not know how much the other things we classically do “wrong” with Cardi puppies (like keep them fat, feed them puppy foods, and flip them schizophrenically from hours on a soft couch to hours of play on hard surfaces) are affecting the eventual OFA-type view. We know that each one of those four things is bad for hips, but they continue to be the way most breeders and most owners raise puppies.

It’s at least theoretically possible that the giant variations within litters are the artifacts of these decisions: One owner keeps puppies lean to the point of being skinny, restricts calories and protein, has multiple dogs, and encourages vast amounts of hard free play in large areas for the majority of each day. The other has a soft, chubby puppy on Eukanuba puppy food; the dog is adored and carried much of the day and has a soft bed the rest of the time, gets two walks a day on a blacktop sidewalk, and on the weekends goes to puppy daycare (on a concrete surface, of course) or the dog park and runs to exhaustion.

We all know how adaptable Cardis are. It’s not like buying a terrier puppy who will make you pay for it if you don’t exercise them constantly–they’ll happily spend most of their day under your chair even as babies. And they’ll happily switch “on” and run for hours on the weekends. But that kind of love is MURDER on developing joints.

So, my research and the ortho vet said, relying on an OFA score is not a great idea and is not likely to get you where you want to be: Producing dogs who will predictably have a long, pain-free life. Remember, that’s what we care about. Long, pain-free life. Not a number, a life. The numbers serve us, not the other way around.

The ortho vet recommended that I look more closely at PennHIP because the database is breed-specific. I agree. Purely on that basis alone it is a better measure than OFA; it doesn’t compare Cardis to greyhounds but Cardis to Cardis.

But there I was stumped again. What I got from conversations with people was what virtually all breeders look at and remember: the percentile score. That magic little bar with the carat marking where your dog lies. Pray for over 50.

And AGAIN, percentile scores were CRAZY. Within individual litters everything from 95% to 20%.

With that kind of wild variation in scores, I began to ask to see the difference in the actual DI numbers.

Here’s the background: PennHIP establishes its percentages based on all dogs of that breed that are submitted. 0% is the highest percentile (the loosest hips in the breed database) and 99% is the lowest (the tightest hips in the breed database). With dogs that have thousands of submissions and that really do have a bell curve of hip health (where most are “OK,” some are great, a few are outstanding; some are borderline, a few are terrible), like Labs and Shepherds, that works out pretty well. Dogs with DIs below the breed average really do begin to represent “bad” hips.

PennHIP hedges all its bets and leaves almost every decision to the breeder. It makes only two real statements: Hips with scores LOWER than .3 represent a very, very small possibility of degenerative joint disease  (DJD) as the dog ages. Notice that they do not use the word “dysplasia.” That’s very smart on their part, because the problem with quality of life is not how loose, tight, shallow, or deep the hips are. The problem is DJD, which in layman’s terms is pain and arthritis. Instead of cartilage moving smoothly on cartilage, bone grates against bone. Range of motion is impaired. Weight-bearing surfaces become painful.

The second thing the PennHIP group says is that scores above .7 demonstrate a very high probability of the dog developing DJD.

Now, immediately, you have to realize that in defining the numbers they’re falling into the OFA trap of basing statements on long-legged, big dogs. The breeds that contributed to this statement were German Shepherds, Labs (a huge number of Labs), Golden Retrievers, and Rottweilers.

So begin the very long process of evaluating PennHIP’s predictive nature with that in mind.

Getting back to percentile scores, where things get wonky is when you have either very tight hips across the breed or very loose hips across the breed, or where there are only a small number of submissions.

For example, if you submitted 50 borzoi films, the DI would range from probably .2 to .26. That means that the ones with the DI of .25 or .26 get percentile scores of 5% or 10%. That could lead you to believe that those are dogs with bad hips. Not so–every single one has gorgeous tight hips. The entire breed has tight hips, so getting a score of 5% is meaningless. This is close to the case in Danes, at least it was when I was PennHIP testing four years ago. Median (50%) was a DI of about .33. 90% was .27 or so; 5% was maybe .4-something. I don’t know if there have been many more submissions since then so the median has shifted, but back then only the most cautious breeders were even using PennHIP so they already had an entire kennel of dogs with Good or better hips. So virtually the entire PennHIP population was healthy.

Similarly, if you submitted 50 pug films, the DI would probably range from .7-.9. So the .7 dogs would be in the 99%, but that doesn’t mean they have good tight hips. The entire breed has BAD loose hips. But, curiously, pugs almost never show any hip pain and they live their obnoxious little lives with their bad loose hips.

A similar thing happens when there have only been a few tens or a few hundred submissions. The submissions will tend to cluster and won’t form a good bell curve, so the percentile is not necessarily accurate.

So when you have a bizarre range of percentiles you have to look very critically at the actual DI scores.

di-chart

The figure above is my attempt to illustrate the percentile versus DI conundrum. Greyhounds cluster at the very top end of the tightness scale, so a low percentage is meaningless. Labradors span a HUGE area, so if you have a 95% Lab it really does have very good tight hips and when you have a 5% Lab it really does have crappy loose hips and a high probability of pain and the need for surgery to fix the joints.

Now let’s consider our little group.

Cardigans have a median (50%) DI of something like .61 or .62 (which would indicate a dog very likely to be crippled or dead by age 4 if you were talking about a Shepherd or a Dane).

Based on looking at a lot of scores, 99% would be something like .51 or .52 and a dog with a really good percentile score would be, say, .53.

BUT (and this is a BIG but) 30%, at least as of two years ago, is .625.

Were you paying attention?

50% (remember, that’s your goal, 50% or higher) is .61…but 30% is .625.  So 20% would be something like .63, and 0% would be a few hundredths below that, right?

That means the ENTIRE RANGE of the breed is .52 to maybe .64 or .65 or .66. That’s a VERY small range; the entire range of the Labs is about .2 to .8!

SO, the question becomes–is a .61 (the average) really a better indication of a lifetime free from pain than a .625 (30%) or a .64? Keeping in mind that a .61 means a crippled dog in most other breeds? If .61 doesn’t cripple a Cardi, does .63?

The DI represents the percentage of the femoral head that can be moved out of the socket. A dog with a .55 has a femoral head that has moved .55 of its diameter out of the socket.

THINK ABOUT THAT. Consider the difference between a .2 and a .8–this is an easy mental exercise. A .2 barely moves out of the socket. A .8 moves almost entirely out. Clearly, one is going to be a better and sounder hip for a lifetime of pain-free work.

Are you prepared to make the same statements about the difference between .61 and .63?

Are you prepared to remove a dog or bitch from a breeding program because its femoral head moved two percent further than your other dog? Are you OK with other breeders telling you that you should do that or you’re a bad breeder? Because that’s exactly what’s happening. Make public that you are breeding a dog with a 20% PennHIP score and see how many love letters you get. Criticism falls like hail and people’s reputations are trashed based on a hip movement of two percent, even though we have no earthly idea and zero scientific evidence that that difference means ANYTHING when it comes to lifelong soundness.

So, then, where the heck does that leave us?

The fact that I’ve just written like fifty paragraphs on this should give you a hint about how conflicted I am about the genuine worth of EITHER method.

And so I have come to a conclusion that is not easy: This is up to you as a breeder. It’s not up to the score. ANY hip score given by an outside agency should be looked at with suspicion (in terms of it meaning the slightest amount about the actual health or life quality of your eventual puppies).

Guess what this also means: You don’t get to make the “She’s a bad breeder because she doesn’t submit hips to OFA” or “She’s irresponsible because she bred a bitch with one hip that was loose” statements. I pretty categorically hate those kind of statements anyway, since if we’re being honest with ourselves they very rarely come from a good place in the soul, but blanket pronouncements are sometimes at least somewhat reliable in other breeds. In this one, I think it’s inescapable that you can be a very, very good, very health-oriented breeder and not be submitting to either registry and you can have a flawless understanding of PennHIP and breed a 20% hip.

You know who the global authorities on Cardigan hip health are? The breeders who have been responsible for their own x-rays and making their own decisions for the last two or three decades. Personally, I’d love to see a Nationals panel of three or four breeders who have been x-raying hips and putting their own breeding programs on the line and ask THEM what a breedable hip is. They’ve probably seen a hundred times more Cardigan hip films than any ortho vet doing his rotation at OFA.

You’ve also got to stop leaning on OFA or PennHIP scores in pedigrees. It was already a iffy idea because of the spottiness of the data; if you face the fact that you have no idea at what point hips are genuinely functional, and that a whole bunch of breeders and owners follow an absolutely ideal recipe for creating bad joints, you need to stop assuming that lot of OFA scores mean a better risk than a few, or that poor scores in some offspring make the dog a bad stud dog.

I can feel the hackles rising, so let me assure you that I do not think that hips don’t matter. I think we must x-ray them all. But I think that analyzing hips is a unique and huge responsibility for the Cardigan (and other dwarfed dog) breeder and if you’re smart you will not leave it solely to outside agencies to decide.

I think the best we can do is to look at as many aspects of the picture as we can, make certain decisions about what we absolutely will not tolerate (keeping in mind that there are some Cardigans with a complete LACK of hip socket) and, if a dog comes back from analysis with looser or shallower hips than we like but is definitely pain free, we weigh whether that dog is actually worth breeding, with the weight against a “yes” decision depending on the severity of the hip “issue.” Call it a serious fault, like a bad bite or a fiddle front. For some dogs, that answer will be absolutely, if you breed to something with really wonderful hip structure (like you would breed a fiddle-fronted dog only to something with minimal turnout, and that may mean that you never find the right match). For others, that serious a fault will (and should) disqualify them from breeding.

My own personal limit would always be at the level of causing pain. If I x-ray a dog at 20 months and I can already see arthritis in both hips, that dog would have to be pretty freaking outstanding to ever consider breeding and then I would do so only for myself or with full and complete disclosure to any other breeders. I already have a replacement puppy clause for pet owners, so that wouldn’t change. If I x-ray at four years and the dog has weird-looking hips but no bony changes, I would feel no guilt about breeding him or her.

I will continue to use tools like PennHIP, and I will continue to get an OFA-style x-ray of each dog’s hips, but I will not allow the percentile score to make decisions for me and I very much doubt that I will waste money on getting an opinion from three guys at OFA who are staring at an x-ray and saying “Wow, corgis have weird hips–I dunno, what do you think? Should we treat it like a Basset hip?” I already have two x-rays to begin my library and I will continue to build that library and continue to refine my decisions. And when I face you, as other breeders and as potential buyers, you’ll know that whatever decision I made is one that I own, and one that I take full responsibility for.

And if anyone catches me making those lovely comments about so-and-so being a bad breeder, slap me.

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17 thoughts on “Cardigan hip scores: A dose of orthopedic reality (Cardigan OFA, PennHIP, DI, etc.)

  1. Don’t worry – I SO understand…

    In our first Pemmie litter we bred a good to a fair (OFA).
    2 pups severely dysplastic – one in such pain he was PTS at 11 months, one who had dual femoral head removal.

    Our first Cardi (hips good, pedigree hips unknown) was bred to an excellent. She had full sisters who were excellent. She produced everything from good to moderate dysplasia.

    A few more years…we get hit by a BUNCH of whammies. The bitch I was refreshing my breeding program with is “mild”. Another bitch we were very happy with got a mild. We bred them both after careful thought. Phoebe of course produced Wally (OFA good) and Golem – both of whom have good DI’s for the breed. She also produced a mild . Grrrr. The 2nd bitch produced an Excellent. All of these dogs have very similar pedigrees.
    We have another dog who has wonderful Pennhip DI’s but failed OFA. He is totally sound at 4 and a terrific mover. What do you do….

    My current bitch has DI’s of .5 and .61 – I was VERY torn on breeding her. She’s the best thing I have produced (IMO). So I go back and forth and back again. I’ve come to use hips as a tool but they are not my do-all-end-all. Too unpredictable.

  2. Oh, my head is swimming, but I agree that this is an important discussion. A long, good, healthy life is the absolute ultimate goal. I enjoy reading your thoughts . . .

  3. WOW-you said a mouthful and I am so glad that you took the 50 odd paragraphs to say it in.

    Thank you for saying it the way you did and no rotten tomatos thrown here. You are absolutely right in saying that it’s up to the breeder to make the determination but passed on all knowledge possible. They are the ones that have to live with the decision and it’s not fair that other’s feel they have the right to make it for you or put you in a corner for your decision.

    Great post!!!

  4. The vet that I use for OFA xrays has seen a LOT of hips. He is used by many many people in every breed, and is a show person himself. His thought is that we need to be putting more thought into WHAT is making a particular hip “good” or “bad”. As in, if the problem is shallow sockets, then look for a deeper socket and not at something like DI. Basically he feels that we should be treating it just like any other piece of conformation, because there are a lot of factors that go into making a hip sound.

    My Leo was neutered not just because his hips didn’t pass OFA (he was Mild), but because at age 2 he was already stiff after moderate to hard exercise. So while I don’t have a problem with people breeding hips that don’t pass with their eyes open, I certainly wasn’t going to breed to HIS hips. Especially since his hip pedigree was poor, and 3 out of 4 xrayed siblings also did not pass. So that’s where the comments about the lack of consistency within a pedigree start to stick in my craw a bit. What I don’t have, however, is examples of a line where you can consistently get GOOD hips, so I see what you’re saying.

    Do Pembrokes have the same issues? I’ve always been confused by how OFA and hip testing is a NECESSITY in the Pemmie world, but not in Cardigans. And with a larger gene pool, many more dogs to test, etc, it seems like we should be able to look at their pedigrees to see what is truly possible with a dwarf breed.

  5. I have no input on hips (I’ve never bred a litter, and am only now for the first time even THINKING about thinking about breeding), but I wanted to say I always really enjoy your indepth, and informative posts. Even if I don’t always personally agree with your exact stance, I am always in so much awe by how well you put forth those opinions, and are so willing to share your knowledge.

    I wish more dog people were like you. I love learning, and hearing others thoughts on matters. It’s hard to learn things about dogs, when so many people seem to keep things about dogs secret, or only in closed, personal circles.

  6. “Do Pembrokes have the same issues? I’ve always been confused by how OFA and hip testing is a NECESSITY in the Pemmie world, but not in Cardigans.”

    I don’t know much about Pem OFA testing (Or hips in general), but I do know that genetically, Pems were bred down to be short, like the Vallhund. They are not genetically a dwarf breed like the Cardigan though.

    Cardigans being achondroplastic, have a differnt hip form than non-achondroplasta dogs (Such as Pems). Pemmy hips resemble that of normal-legged breeds, because genetically, a Pem is a normal legged breed, bred to be shorter stature, based on my understanding of the breeds genetics.

  7. Wow, what a great post, Joanna! And a post that is near and dear to my heart.

    I’ve been very open and honest about my girls OFA status and Pennhip scores. I’ve been deliberating her breeding status since then (summer of 08) (and she also happens to be a daughter of Mandy’s bitch, Phoebe – mentioned above).

    As of June 08, according to Pennhip, the breed median for Cardigans was .61. My bitch came back with one hip being .63 and one hip being .42. OFA rated her as “Mild” with subluxation checked. What did that tell me? NOTHING. So I went and had Pennhip films taken and submitted. I learned a lot more about what I was ACTUALLY dealing with there.

    I’ve received a lot of “looks”, if you will, about even considering breeding my bitch, based on the fact that OFA says she has “Mild Hip Dysplasia”. She is 2.5 years old and completely asympomatic. She’s in no pain and for goodness sakes, she’s .02 away from the breed median in her one hip. Perfectly fine in the other. Otherwise, she’s a beautiful animal with many breed virtues. yet others continue to give me that “look”.

    I know some breeders may x-ray and not submit… that’s their choice. however, I wish more breeders would TALK about the x-rays they’re not submitting. I wish they would SHOW those x-rays (for goodness sakes, we’re in the digital age people). There are a few dogs in some “lines” I’d love to consider, but when I cannot get so much as a response from breeders about hips and whether they’ve been even examined, I can’t risk that.

    Being a new breeder, but having been in the breed for 7 years, I have been as open and honest about my bitches hips as humanly possible. When I had a breeding lined up, I had it spelled out as clear as day on my website what my situation was, what the numbers were, and how I felt. I, like you, will stand behind any puppies I create. That’s our job as a breeder, right?

    I’m disappointed in many of the longer time breeders who are less than open and honest about their hip results. I’m disappointed that many aren’t willing to discuss these results. Shouldn’t we all be able to learn from one another?

    Wonderful post, as always, Joanna!

  8. Sometimes I wonder if we shoudn’t start some kind of a cardi hip site. Nothing official, just a place where people can post all their xrays, so we have something to look at.

    Kathy Carter has many on her website (Joanna and Nancy both pointed me to it) and I know they were helpful.

  9. Hmmm, maybe that’s something we as independent breeders can do… start posting not only results we may get on tests, but the films as well…. Like I said, we ARE living in the digital age, afterall 😉 Worst we can be blamed for is honesty….

  10. Scientific text I’ve seen quotes Pems as being chondrodystrophic dwarves, while Cardis are being quoted as being achondroplastic dwarves.

    Medical dictionary text quotes:

    Chondrodystrophic dwarfism: A congenital dwarfism in which the disturbed development of the cartilage of the long bones arrests the growth of long bones, resulting in extremely shortened extremities.

    Achondroplastic dwarfism: A congenital dwarfism resulting from a failure of cartilage to normally develop into bone, especially cartilage on the ends of long bones.

    I’m no expert on this topic (Far from it), but genetics text I’ve seen, report Pems as being a differnt form of dwarfism as Cardigans. I very well could be misunderstanding of the texts, but this has been my understanding of the differences between Pem, and Cardi dwarf genetics.

  11. I think we need to be really careful when we generalize from human dwarfism to dog dwarfism. They’re not the same thing and in fact show no genetic cross-over.

    The human types are spontaneous genetic mutations in the FGFR-3 gene that result in offspring that looks totally different from the parent, and those little people themselves can produce offspring that are average height.

    In addition, achondroplasia in humans is lethal when the human gets two copies of the gene. No copies – average height. One copy – achondroplastic dwarfism. Two copies – death.

    That’s not the way dog dwarfism works (it IS the way cow dwarfism works, though). Dogs have the extremely shortened long bones and the brittle cartilage, but they inherit it in a completely different way. Only VERY rarely is it a spontaneous mutation. And it reproduces like any other physical trait: If you breed a corgi to a Border Collie, you get dogs with intermediate-length legs and some bowing. If it worked like human achondroplasia you’d get half a litter with extremely short legs and half with Border Collie-length legs.

    Also, achondroplasia in dogs is inherited without danger; it reproduces predictably and doesn’t kill puppies.

    The final difference, and I think it’s very important, is that in dogs the syndrome is not associated with other medical problems. In humans it is rare to have only the shortened limbs. You tend to also have chest abnormalities, limited range of motion, discordant growth that causes twisting of the bones, a larger head than usual, and shortened finger and toe bones. In dogs, the only things that are affected are the long bones of the legs.

    What we have in these dogs–Skyes, Pems, the “shortie” Jacks, Cardis, Sussex, etc.; there are MANY–is called achondroplasia because the word means, for lack of a better term, “Weird cartilage.” All these breeds have odd cartilage behavior that results in shortened long bones. Don’t fall into the trap of generalizing it to the entirely different disorder also called achondroplasia that is found in humans.

    (This is like “parvovirus,” by the way–parvovirus just means “small virus.” Parvovirus in dogs refers to the deadly disease that attacks rapidly dividing cells in the intestine and heart. Parvovirus in humans causes a rash and a fever and is largely harmless. It’s also called Fifth Disease, for all you moms and schoolteachers out there.)

  12. An excellent journal article on this subject was just published last October:

    http://www.biomedcentral.com/1471-2156/9/67

    FGFR-3 is highly conserved in dogs–and not responsible for the size variations seen across breeds (nor responsible for the phenotype of the chondrodysplastic breeds).

    I suspect the paper which DOES implicate the genetic inheritance responsible for canine dwarfism will be published very soon–I’ve already heard a talk on the subject and so it’s just a matter of time before it makes it into publication.

  13. I didn’t have time to get to reading the entire post and comments until today. I’m glad to see that Baledwr already commented.

    For the record, I have seen many OFA films of Cardis, Pems, and Aussies. I thought that Phoebe’s hips would pass with a “fair” and so sent them in but OFA ratings seem to be . . . well, I don’t want to say “random” so let’s say “inconsistent”. As Phoebe is now 7 and still a great mover with no stiffness I don’t believe that she has an issue. I have thought about going back and getting a PennHip score just for reference.

    I plan to continue to use PennHip, but don’t plan to rely on OFA rating in the future. I placed Digger due to his PennHip scores of .71 and .57. I would probably have been ok with something in the .65 range, but over .7, well I just couldn’t go there. I do still have regrets and want to second-guess myself because of other things I thought he could offer.

    Frankly, IVDD is a much more important issue to me. Ever since OFA-good Juneau went down in the back before he was 5 I’ve wondered “what’s the use?”

  14. You might all think about submitting hip xrays on your older Corgis to give OFA something to work with if you are not happy with the results you are getting from them on your younger dogs. No arthitic or degenerative changes on your 6, 7, 8 year olds will get passes and legitimitize your theories of Corgis having weird hips that remain sound. And just so folk of other breeds don’t take away the wrong message, this appears to be peculiar to Corgis and they are a smaller breed and may function fine even with true hip dysplasia, but this is not applicable to other breeds, especially heavily built ones that truly suffer with dysplastic hips. It’s well worth OFAing a dog being considered for breeding so you know what you are working with and then judge accordingly. I can’t help but think though that not using dysplastic dogs would go a long way in decreasing the genes cause dyplasia from the gene pool over the long haul. We’ve never really reached the point of 100% compliance in breeders and so the CHD genes just keep being circulated in the gene pool. I hate to think people are getting discouraged by some of what is online and mistakenly see OFA as an effective method simply because not all xrays are submitted. OFA is in the business of identifying normal hipped dogs for breeding purposes not the state of hips in entire breeds. It would be nice to have his extra data but really all a breeder wants to know is if their dog is normal and the strebgth of the family history. If you look at http://www.offa.org/monograph2006web.pdf you will see stats that show the improvement in excellent hips across breeds – and obviouly mostly all passing hips are submitted so OFA is having a positive influence at least in regard to passing hips. Without all the fails being submitted we don’t know how well it’s working to reduce CHD. But that is not it’s purpose. It’s purpose is to certify normal hips for breeders.

    I’ve read HERITABILITY ESTIMATES OF HIP SCORES IN THE GOLDEN RETRIEVER BREED study. I noticed that they did not use OFA readers but board certified radiologists using the OFA criteria – not sure but that might have made a difference.

    A few other things to think about:

    “Gene markers have been found for hip laxity in some breeds and the left hip joint has a higher percentage of frequency than the right hip. Laxity is under genetic control and not the same as canine hip dsyplasia ( CHD). Some dogs with CHD occur concurrently with those that have hip laxity, but the two are genetically separate entities. (from http://clubs.akc.org/brit/VetArticles/PennHipVsOFA.htmd

    “Laxity is generally considered to be one of the earliest pathologic fi ndings in HD. The fact that joint laxity plays a role, but is not the only factor, in development of hip dysplasia and its secondary changes of degenerative joint disease has been recognized for over 30 years.” (from http://www.offa.org/monograph2006web.pdf)

    “It is important to understand that heritability estimates do not refer to the degree of inheritance, but rather to the degree that the additive genetic component is reflected in the phenotype …. Breeding based on individual phenotypes appears to be the method used by most breeders, as available information on relatives is somewhat limited. For traits considered to have moderate heritability, this approach will reduce the frequency of an undesirable trait in the progeny, but progress, while substantial, will be slow. Information on siblings of an individual animal, plus information on
    the siblings of parents and grandparents, makes it possible for the breederto apply greater selection pressure against the disease. This results in selection of animals with more ideal breeding values and provides a more rapid reduction of the undesirable trait in the breeding program. ” (from http://www.offa.org/monograph2006web.pdf)

    There are ongoing debates about which is better OFA or Pennhip – see http://www.workingdogs.com/ofa_penn.htm for both sides of the issue.

    I still come back to the value of submitting hip radiographs of older dogs if folk feel OFA is not reliable at 2 years of age and choose to go with their gut instinct in deciding to breed young dogs that don’t pass OFA at 2. OFA is interested in getting second submissions and will not rate a dog down based on an older xray, but they will rate a dog up, so really what do you have to lose?

    • Just FYI, here are aspects I think are problematic:

      1) Hip dysplasia genes? Really? So dogs that are heavy and big-boned have fifteen times more hip dysplasia genes than dogs who are light-boned and grow slowly? We may discover some genetic influence in terms of extreme results within certain breeds, but if you look at the common-sense aspect of it, hip dysplasia is a developmental disease associated with the growth of heavy dogs. OFA researchers INSIST that it’s a genetic disease that exists apart from the dog’s body type and growth pattern, but that just doesn’t jibe with the fact that breeds that have come from identical founding populations show a rate of dysplasia that is strongly associated with how heavy they are, or with the studies that show drastically reduced dysplasia rates when growth is rigidly controlled.

      2) The “corgis just have funny hips and they do fine with them” line is not mine; it’s from an orthopedic surgeon.

      3) I will definitely be checking up on both Clue and Bronte as they age in order to see if they have any arthritis (Clue in the pelvis, Bronte in the stifles) that I have to aggressively treat. So I’ll be able to see their hips as they age. But that won’t change the fact that while an OFA-type evaluation may be a decent picture of a particular dog as it stands on that day, the important thing is whether that assessment translates to less hip dysplasia in the next generation. To answer that, I’m seeing OFA make a lot of lofty statements and grand opinions, but very little actual progress is shown in any of the breeds.

      4) I’m very aware of PennHIP and my assessment of PennHIP in corgis is in this same post.

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