If I choose to only do pennhip this time around....will this be enough for other breeders in terms of a clearance when breeding time comes?

Will it be enough for all clearance reasons like joining a Lab club....selling my pet pups and so on?

Tanks

It certainly would be enough for me. Anything in the 30th percentile and above is just about always OFA Good. The good thing about PennHIP is you can get the answer before 2 years.

That said, some people are always going to want OFA, so if you have a boy you hope will be used at stud, you may have to do OFA too unless you are in the high percentiles. Plus people will look for elbow clearances too.

Does Penn Hip eliminate the necessity of getting both prelims and finals done? If so then in the long run it must be cheaper.

PennHIP done between 16 and 20 weeks is considered good for the life of the dog. Any changes should be minimal. PennHIP's idea is to use only the top half. That is really very strict. I would probably do OFA if the score was in the 30th percentile. 40th percentile and above, I would not bother.

If you do a radiograph on an immature dog, whether for PennHIP or OFA, what you will get is an evaluation of an immature dog. There are reasons why OFA selected 24 months to let dogs complete their growth and development. PennHIP results can change with age, as many who have had them redone as adults will testify.

Scores of .30 or .35 is what is considered good, of course something like .20 would be excellent. Something in the 30th percentile is not good.

As with any clearance that has a mature or proper age attached to it, doing any clearance too early may not reap you correct results.

It's the same as doing prelims.

I have seen a lot of x-rays from dogs between 16 and 20 weeks and they all look great. Even for dogs with really bad PennHIP scores.

You must like to breed displastic dogs! 30 percentile means that 70% of the labs tested have better hips than yours. If 30 percentile is good for you, your Pennhip clearance would not cut it to use my stud dogs.

80 percentile is similar to OFA Good, not 30th percentile.

Got news for you. I have records of 14 dogs in the 30th percentile. There was one borderline, one mild and the rest were Good.

Being Pennhip is more accurate I would think that your OFA readings would be inaccurate if your getting from Good to fair with a 30 percentile Pennhip.

In the OFA system there are false-negative rates of about 83% in 6-month-old German Shepherds, but in the PennHIP scheme, the rate is only 12% in 4-month-old dogs and 0% at 6 months (as compared to the readings at 24 months). The OFA approach on 4-month pups gave a false-negative rate of 24%, double that of the PennHIP compression-distraction method. Even at 6 and 12 months, the OFA-type predictive tests gave false-negatives of 15% and 12% and the PennHIP stress-radiographic method showed zero false negatives for 6- and 12-month old dogs.

Pennhip website says:

It is recommended that breeders choose breeding stock from the tightest 40% of the breed (meaning the 60th percentile or better), thereby maintaining an acceptable level of genetic diversity while still applying meaningful selection pressure. By breeding only dogs with hips above the breed average (60th percentile or better) the overall breed average will move toward better (tighter) hips from one generation to the next. Clearly the more selection pressure applied (stricter selection criteria), the more rapid the genetic change.

I appreciate that you are paraphrasing from a specific PennHIP document when talking about "false negative" results at various ages. You reallly need to analyze the report and the methodology used to derive the percentages. The ANOVA method used is not appropriate for the type of data and it does not accurately reflect the realiability of the radiographic evaluation comparisons. Sometimes you can't just take what is implied without knowing enough about the statistics and methods to determine whether the conclusion can be supported by "common sense." As I keep saying, get the facts and let them speak louder than rhetoric.

Actually, exactly what it says on the PennHIP report is:

"NOTE: As a minimum breeding criterion, we propose that breeding stock be selected from the population of animals having hip laxity in the tighter half of the breed (to the left of the median mark on the graph)."

That is NOT the tightest 40%. As far as the OFA Good dogs in the 30th percentile, that says a lot about OFA. The two do not equate.

I ended up doing both on the dog I use for stud as people told me they wouldn't accept PennHip scores .. I would though!

Interestingly enough one of my dogs came back with a 30th percentile and my vet (who is PennHip certified) was QUITE emphatic that anything less than 50% NOT be used for breeding) I never had OFA's done on him and have never bred him .. now I'm hearing he would have been "OFA Good"???

OFA and PennHIP scores cannot be compared, especially when you start referring to percentages because percentages are breed specific. The tightest 50% in Bulldogs might still contain a great many dysplastic dogs.

PennHIP does now recommend the tightest 40%, but again this is all relative to breed. Breeds such as borzoi have such a low incidence of hip dysplasia that nearly all of their breed have hips tighter than the top 20% of Lab.

The reason to use PennHIP is because you can actually consistently improve the tightness of hips in offspring, not just "certify" the hip health of a particular dog at 2 years old.

The form that says they recommend breeding only the top half was from March 10, 2010.

Here is a quote from the PennHIP.org website:

"To avoid these potential problems accompanying ‘extreme’ selection, PennHIP suggests a more ‘moderate’ approach which goes hand in hand with the PennHIP testing. Particularly in breeds with few or no members having tight (OA-unsusceptible) hips this moderate approach is preferable. In such breeds it is recommended that breeders choose breeding stock from the tightest 40% of the breed (meaning the 60th percentile or better), thereby maintaining an acceptable level of genetic diversity while still applying meaningful selection pressure. "

The website has been updated and has an excellent podcast in which a rehabilitation specialist interviews Dr. Gayle Smith about PennHIP. The podcast lasts about 30 minutes and discusses the latest research about DJD and PennHIP, including an article that will appear in JAMA.

Why do I think the top 40% recommendation is not directed to labradors? Do labradors fit - "breeds with few or no members having tight (OA-unsusceptible) hips" ? Hardly.

You really can't compare PennHIP ratings to OFA. I had one in the 40% get an OFA Fair, one 50% got OFA Good and one >90% got OFA Good. Nothing of mine that scored below 40% for PennHIP ever passed an OFA. I would not approve a bitch for breeding with less than 50%; unless they had a passing OFA also.

Listen to Dr. Smith's Podcast (on the PennHIP website). Yes, a recommendation of top 40% is appropriate. Labs and Goldens are specifically mentioned. OA is not yet a "fixed" characteristic of Labs and Goldens, but close. Listen to the podcast. Very enlightening, especially about breeding OFA Excellents and the fact that the broadcast is also directed to pet owners.

I guess we all tend to pick and choose whatever supports our point of view. I too have listened to the podcast. Here is a direct quote from the podcast.

"So long as you, as a breeder, are breeding dogs tighter than the midpoint, tighter than the average Labrador or Golden, you are imposing so called positive selection pressure and obviously, the more your breeding dogs deviate towards tight hips, the more rapid the genetic change. So we are not suggesting that you just narrow the genetic lines dangerously and lose other desirable traits, and that's a common misconception and a common criticism and it's not what we are suggesting at all. Within any given birth year or generation, using the PennHIP system, fully one half or 50% of the dogs born that year would be suitable breeding candidates."

Perhaps we pick and choose based on how important we think it is to improve the breed hip health.

"Half a loaf is better than none."

My preference is to not turn people off by making things seem more difficult than necessary.

For those breeders a few slices short of a loaf.

I have an OFA Excellent bitch that had PennHip done at 16 weeks and her numbers were .64 on the left and .59 on the right. The percentile was 20th at that time.

I am sorry but she does not have lose hips. She is know almost 3 years old. She is a beautiful mover. She was sedated for her OFA finals and the vet who did the xray felt she had nice tight and beautiful hips.

I will not allow my stud dogs to be bred to bitches with only PennHips unless she was done after 2 years old and I actully got to his her films so I could see what her hips looked like.

JMHO

According to Gayle Smith, you might think of PennHIP as evaluating a risk factor for developing osteoarthritis over the life of the dog or in the offspring. Just because you have an OFA Excellent at two years old does not mean that the dog will not develop osteoarthritis over its lifetime or produce osteoarthritis in its offspring. In a study of 469 dogs of all breeds with OFA Excellent hips, the likelihood that the offspring would develop osteoarthritis was 56%.

OFA looks at the hips on the day the xray is taken--PennHip is more predictive in nature. The looser the hips are, the more they can joggle around in the socket and be traumatized, therefore leading to arthritis later in life. You can not see any looseness just by looking at the dog! It has nothing to do with movement. When breeders learn to use the PennHip as an aid in determining the true status of their dog's hips, we will decrease the incidence of hip dysplasia in the breed.

"AMEN" to that Kathy!!!

A radiograph is simply a shadow image snapshot. It is affected by exposure, pose (positioning) and condition of the subject - just like any snapshot. All systems can only look at the image on the day it was taken. PennHIP attempts to predict the future based on the degree of laxity in that snapshot. OFA considers the laxity as just one important factor that is used in grading the hip at the time. A dog with laxity showing on the radiograph will get a lower rating (including failure) than one that shows very little. Either way, the film only shows what is apparent at the time.

While it is an important aspect of hip fit and potential wear, laxity changes with condition. In fact, it is the graded aspect that changes most from one radiograph to another of the same dog over time according to longitudinal studies by OFA and Michigan State University. A young dog that is graded fair due to laxity may receive a good or even excellent rating at age two. A dog that lacks exercise may show laxity in one film and show very little a few months later after normal conditioning. A radiograph is just a snapshot of the shadow of bones at one moment in time - nothing more or less. The major differences between various systems are what humans try to extrapolate from that snapshot.

Please give the actual published reference for this study. I would love to see the data set that can predict what a dog might produce over a lifetime - especially when it involves different breeds with different incidences and expressions of CHD in the base gene pool.

Cited by Dr. Smith in the podcast in which he was interviewed. Check the PennHIP website someone else posted. From the rest of the podcast, I'm guessing that the study will be published in JAVMA later this year. Just a guess.

For the 'science geeks' like me, you might find this abstract from the 2005 Tufts Conference on genetics and heritability of DI or subjective hip score interesting. There are some great charts and examples that are worth considering as you look to breed.

haha misses my point and probably is not into puns. Dr. Smith is good with "half", as in the top half.

The recommendation of the PennHIP system is to breed only individuals in the top half. That is a sound recommendation. However like all recommendations or rules of thumb, they are just that.

I'd like to point out the similarity of two such rules. OFA - A dog cannot be certified until it is 2 years of age. Nobody would quarrel with the idea that a dog's hips do not change overnight. If x-rays were taken a day before the 2nd birthday, OFA would not give finals based on them.

PennHIP - By the same token, a dog's DIs are used to determine the percentile. Since we are dealing with decimals, a difference of .01 could make the difference between a score being in the 50th percentile and the 40th percentile. Most people would have a hard time with excluding a dog for a difference of .01

More people are becoming open to the idea of PennHIP. Initially, many breeders viewed it as "just one more thing to flunk" and did not want to risk more bad news. That is not hard to understand. And that is exactly why I object to "PennHIP is Better" using something out of context, saying that the guideline has changed. It has not. If anything, that only makes people more uncomfortable and works against the increasing acceptance of PennHIP.

I would like to try to address the laxity idea. Can you imagine a exquisitely engineered Italian or German sports car? It could probably be run under extreme conditions for thousands and thousands of miles and be ready for more. Those wheels could keep performing well. Can you imagine the little red wagon you had as a child? Not much engineering going into that model. Parts did not fit precisely and there was lots of wobble. Could it have gone thousands of miles? Of course not. The parts wear against each other and fail with extended use. The precise fit in the car keeps it moving smoothly.

One interesting thing in the podcast refers to some dogs they are following with extremely tight hips. Those dogs never develop any osteoarthritis! Most dogs will develop osteoarthritis to one degree or another if they live long enough.

Listen to the podcast and try to keep an open mind.

http://specialpetsspecialneeds.com/2010/02/02/episode-23-dr-gail-smith-talks-about-the-pennhip-radiographic-technique/

Thank you for the link. I read the report, but have to read the full articles of several other studies referenced. I don't have all of them in my personal library.

I found some of the same sort of misuse of statistics observed in other reports that makes me mistrust PennHIP conclusions. Comparing the heritability of DIs of one (1) litter of GSD pups whose parents were selected from the tightest 5% to the overall heritability of OFA hip scores from 200+ litters across 4 breeds where parents included varied ratings is very misleading. The results should be better when narrow selection is used. However, stating that a .26 heritability (an enviable figure in most circles using only mild selection pressure) was "insignificant" is irresponsible and self-serving.

Using any sort of selection method will improve outcomes toward that criteria. PennHIP can proudly claim that using DI for selection pressure will improve DI in future generations - that is a logical conclusion even without statistics. However, I fail to see why they want to misuse data and disrespect significant research that shows other selection measures also improve outcomes for those measures. One does not have to "discredit" OFA in order to establish the relevance of PennHIP. The two systems use different criteria and both seem to have been successful at improving the hip status for breeds and breeders who use evaluations intelligently. It is just harder for me to trust those who repeatedly twist statistics to promote their own self interest.

Not necessarily. If the selection criteria (method of evaluation of hips) does not have validity or reliability in measuring the heritable part of a trait, the outcome of using the selection criteria will not statistically be improved. So who is twisting statistics?

Can you spell condescending?

In response to the initial poster, I think that will depend on the age at which you do the PennHIP film and the results. I wouldn't accept a film done at four to eight months with a 50th percentile rating. I would likely accept one done at 24 months with a 90th percentile rating. If you are using a system that doesn't make the breeding evaluations for you, then you have to know enough about the system to reach those conclusions independently. Fair enough?

To tidy up a few other matters:
PennHIP wrote: "In a study of 469 dogs of all breeds with OFA Excellent hips, the likelihood that the offspring would develop osteoarthritis was 56%."

There is no possible means that one can take a specific 469 dogs of various breeds and predict what they will produce over a lifetime when you don't know what they will be bred with. This statement is either conjecture or misrepresented.

Breeder later wrote: "Most dogs will develop osteoarthritis to one degree or another if they live long enough."

If this is true, it would certainly explain the previous quote from PennHIP. In fact, it would appear that a prognosis of only 56% development of osteoarthritis compared to "most" would be an improvement. That would clearly endorse breeding from OFA excellent stock to reduce potential problems in future generations. Perhaps this was really the point of the study referenced by PennHIP and was misused to make a positive outcome appear to be negative.

It is human nature to attempt to compare and contrast objects and systems in our lives. We must be careful to put the "contrasts" in the correct column and not use them as comparisons. Such thinking does not support valid decision making or serve the breeds we love.

I quoted directly from information from the PennHIP podcast. The entire study results have not yet been published. When they are and when you have read them, I hope that you will revisit your speculations about the inaccuracy of the outcomes.

I stand by my statement. Hip evaluation is a phenotype selection - regardless of the criteria used. Consistently selecting for a particular phenotype will skew outcomes toward that criteria. That is how individual breeds were developed in the first place. You don't need to abuse statistics to grasp the common sense reality of that.

I really look forward to discovering the scientific methodology for predicting what a dog's unborn, future offspring will develop without knowing where or how the dog will be used for breeding. Perhaps it is the "crystal ball" method? Please post the exact reference when it is published. Until then, it is just hearsay - not to be confused with fact.

Rightly or wrongly, statistics is not commonsense to most people.

Through breeding colonies and statistical analysis PennHIP evaluations have been found to be highly correlated with a genetic risk factor for OA.

But regardless, the study will be published later this year. Perhaps you can write a letter to the editor with your critique after you read the research.