According to OFFA, "Fair" is comparable to "Normal", not "Fast Normal" in SA a stamp. "Fair" is the lowest among normal hip.
For the purpose of breeding, the OFFA specifically suggests to not regard "Fair" as unsuitable for breeding. It says that it is better to breed a dog with Fair hips itself but with an established normal (E, G or F) hips ancestory than one of Good or Excellent hips but of unestablished ancestory, with missing OFA records of parents and grandparents.
Do you agree with OFFA?
I have seen two Excellents from two Fair parent pairs. It seems to me that the significance among the three normal categories in OFA hip ratings is not great.
Keep in mind the 2 leading causing of HD are 1. Genetics & 2. Nutrition/Diet.....so let's say that a Sire/ Dam OFA fair because they did not get the required amount of nutrients during the key phases of bone development, but their offspring did and they OFA excellent...then nutrition is to blame...
I too have seen "fair" sire/dam's, and their offspring OFA "good" or "excellent", but when it comes to breeding I personally would not breed fair-to-fair...if it is genetics then why not increase your odds of better hips...do I agree with differences in ratings? yes and no..sometimes it's hard to tell if the femur head is deformed, or if the hip socket is too shallow, I wouldn't sweat a "fair" rating, there's a fine line between good and bad hips. You ask 100 different dog trainers what is the right way to train a dog, I guarantee you will get 100 different answers
I disagree. The a stamp is typically less diagnostic because it is taken at one year. The OFA requires the dog to be at least 2 years old which is an age where better dignoses can be made.
What this means is that the range of variance in the SV xray reading is much greater long term than for the OFA reading. For example a SV a stamp of "A normal" can end up with a range all the way from OFA excellent to mild dysplasia at 5 years old. My vet who is now retired xrayed many german "a stamps" for OFA from folks who imported them and wanted to see how the hips and elbows looked at two or over and found a very great variance in these "a stamps". He showed me some examples which were surprising to me, "a normals" which xrayed to appear mildly displastic, and some appearing to be OFA fair, good or excellent. This vet's positioning was the best , that's why I drove so far to use him--he did of lot of GSDs for many years, of import and domestic breeding (he used two helpers and the owner and used a remote footpedal to activate the xray machine while he did the main positioning. To me an "a stamp" should be repeated at two years old if one is going to use the dog at public stud. This increases the diagnostic value substantially. At least 25% of the imported GSDs he xrayed the elbows on had DJD, a surprising frequency.
O.F.A. "Fair" is a passing score, and the dog is breedable if most of its siblings and ancestors are passing dogs as well. Sometimes a "Fair" can improve to a "Good" if the positioning is better, but usually it is what it is. The score of "Fair" is interpreted by the O.F.A. to be "suspicious of hip dysplasie" meaning that it could worsen to the end that it develops degenerative joint disease, essentially arthritis.
What is it's S.V. equivilent? That depends on who you ask and their experience with the two (2) systems. In my opinion, it lies somewhere between "a"1 and "a"2. I will take Preston's statements further and say that I will trust an O.F.A. "Fair" at the age of twenty-four (24) months much more that I will trust an S.V. "a"1 or "a"2 at twelve months because of the difference in bone and joint maturity.
And yes, I agree with the O.F.A. as far as the value of siblings and ancestors rather than just the examined dog. That is the way the S.V.'s ZW system works, but of course the S.V. uses a formula to calculate the predictability of hip quality and assigns a numerical value.
Folks can think what they want, but the facts remain that a fair number of GSD imported into the USA with the "a normal" SV hip rating have mild dysplasia when xrayed or penn hipped at two years old or greater. I can't say for sure about A2 or A3 SV hip rated dogs when xrayed at two or older because I haven't seen any of those xrays for them at two years or older, but I don't see how they could have less statistical variance. Putting your head in the sand won't help the breed any. Ignorance and feelings is no substitute for knowledge. In actuality, it always comes down to any specific GSD and how they xray at 2 years old and later as they age. Heritability estimates are probabilities and the specific animal can get a unique gene combo transmitted to him, a polygenic set of at least five recessives which can stack the deck for or against hip cleaness.
I find the high frequency of DJD in elbows (which is anything less than A normal) in West German blooded GSDs appalling. It is now well known by researchers that elbow health requires much more careful selection and that means best to use only a1 normals elbows for breeding GSDs.
Yes, family tree hip health frequency is important in the probability of any specific GSD producing clen hips even if his are very clean, but it is only an estimate. It always depends on whether the dog is dominant for clean hips or not and what mate he is bred to. As many now realize for certain, VA Esko Danischen Hof was a dominant producer of clean hips and this came from the dominance for clean hips of his dam's line which was transmitted to and through him.
Held and mirasmon, rather than spouting belitteling comments, how about stating rational reasons for disagreeing with me.
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