Elbow Dysplasia

[Nebulosa]

Originally Posted by rolf

Thanks nebulosa, But don`t understand what you mean with these numbers and I have no idea what norberg angle is ? ...But I have been reading some articles in the past, stating that HD(I don`t remember if ED also were mentioned) is many times not that a big problem for the dog, if it have strong musculation and live a healthy life(not saying that it is never a problem for some dogs or is does`nt matter for breeding).

Lets try to put it in percentage.
Hereditability of HD: 20% to 40%
Herebitability of ED: 40% of 100%
Depending of the breed.

In easy words, Norberg Angles are the meassure of the angle formed by the center of the femor head with the acetabulum border, those angle is one thing evaluated in the HD exam and different angles results in different HD results.
Basically, when more far the femoral head is from acetabulum, less angles it will have, worst result the dog will have.
Actually, this metod works pretty well and really helps the selection of the dogs, for sure it will show a displasic dog without any problems as it will show any kind of degeneration already existent, but the polemic of the metod is that the laxity of the cartilage cannot be really evaluate in the X rays, so we can see some cases of females in heath who had receive bad results in the first X rays, and a normal one with nice results about 2 months after it because the hormonal incluence in the cartilages, we also have few cases of very old dogs with bad norberg angles but no damage at all in the femor, but this last one seems to be pretty rare.
Remembering that now we have the Distraction metod ( pennhip) which evaluate the laxity, but unhapply its still not avaible for every country like the well know X-ray metod.
I think this part already reply you the next one, what is the difference in a HD C dog and a ED 1 dog, as the two are considerated displasic

Maybe I am stupid, but HD = Hip Dysplasia and ED = Elbow Dysplasia, so it is Dysplasia in the hips and in the elbows, how come one is worser than another, I mean it is the same thing, but in different places, so the degree of how bad or good it is, must be in the scales HD = A, B, C, etc. and ED = 0/0, 1/1, 2/2, etc. ? ...or am I totally wrong ?

Rolf

A dog with ED 1 was evaluate like that because the veterinary already found a degeneration, that means a dog with ED 1 already have the signals of degeneration, like Osteophytes or sclerosis while an displasic C dog can receive those results without have any degeneration, but bad Norberg angles. When you have the Elbow signal and results pretty clear, you don't have such certainly in Hips, don't wonder why on HD you have some degrees before consider a dog affected or not, while on ED or the dog is clear or he is already affected and the others results will only show how worst it is.

[woland77]

Originally Posted by Nebulosa

Hereditability of HD: 20% to 40%

...this is wrong...HD ever start from genetic heritage...development of the disease for 80% depend on external factors!!

is a big differences!!!!

"...a genetically healthy dog can not get HD disease from external factors.."

i must put bibliografy again?

[Nebulosa]

Originally Posted by woland

...this is wrong...HD ever start from genetic heritage...development of the disease for 80% depend on external factors!!

is a big differences!!!!

"...a genetically healthy dog can not get HD disease from external factors.."

i must put bibliografy again?

Where the bibliografy you send have the hereditability of HD? I only saw an adversiment about it, almost a cultural one for breeders.

OBJECTIVE: To determine incidence, risk factors, and heritability estimates of hind limb lameness caused by hip dysplasia in a birth cohort of Boxers. ANIMALS: 1733 Boxers from 325 litters. PROCEDURE: Status of Boxers with respect to clinical signs of canine hip dysplasia (cCHD) was registered during an 8-year period. Survival analysis accounted for dogs lost to follow-up. Effective heritability for developing cCHD was estimated by use of a proportional hazard model on the basis of the Weibull distribution. Parametric survival models were developed to identify the influence of potential risk factors. RESULTS: Cumulative hazard rate for cCHD from 7 weeks to 8 years of age was 8.5%. Dogs that were kept on a floor covered with a slippery material were 1.6 times as likely to develop cCHD, compared with dogs kept on a nonslippery floor. Risk of cCHD doubled in dogs from litters with a high preweaning mortality rate. Dogs that were neutered at 6 months prior to a diagnosis of CHD were 1.5 times as likely to develop cCHD, compared with sexually intact dogs. Dogs >5 years of age were 1.8 times as likely to develop cCHD, compared with younger dogs. Estimated effective heritability of cCHD was 0.11. In terms of the risk of cCHD in progeny, mean estimated breeding value (EBV) of the 10 best and 10 worst sires was -0.32 and 0.42, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Registration of Boxers that develop cCHD may provide a strategy for disease prevention. In addition to diagnostic evaluation of radiographs, sire EBVs provide useful information for breeding selection decisions.
http://www.ncbi.nlm.nih.gov/pubmed/1...?dopt=Abstract

Its only one studie who shows numbers like that, if you search you will find much more.

I no moment I said HD was not a genetical illness, but the truth is that external factors make a huge difference in the results, of course a dog without genetic for displasy will not show it BUT nothing impeach this dog to have a subluxation because the place it lives or by accident, wrong feed with wrong exercices can cause artritis, all those cases will be considered displasic in the exams, even if those animals have no dysplasi in their genetic, of course we will not see an A dog turn E because it, but we can see non displasic dogs with B or C.
No wonder why we have so many grades for HD.

Yes, the dog cant get displasy by external factors, but he can have artritis and artrosis by it, and it will change the HD evaluation on the official results also as a non displasic dog with bad norberg angles.
In the same way you can get a dog which have a strong genetic for the problem, but because the threatment it will receive B or C.

Well, we have no doubts about how 20 to 30% of genetic can make a huge difference, you can see it principally in the behaviour of working dogs, now you can imagine how much difference it can make when its 40 to 100%.

[SERENA]

A harmful environmental factor in the pup is genetically able in a healthy dog as HD regards, to provoke a arthrosic degeneration of the hip (owed to traumas and bacterial infections, ect ect), very similar to the HD for symptoms, but well distinguishable in the x-ray examination.

[woland77]

Originally Posted by serewolf

A harmful environmental factor in the pup is genetically able in a healthy dog as HD regards, to provoke a arthrosic degeneration of the hip (owed to traumas and bacterial infections, ect ect), very similar to the HD for symptoms, but well distinguishable in the x-ray examination.

Paula, this is taken and translate from my post of yesterday and those words are taken from e-mail of Dott. Vezzoni, president of ufficial reading central FSA (the first central in Italy), and the same word i have heard at Dott. Pedrani (CELEMASCHE, second and last central in Italy) at "HD conference" on december 2008.

Arthrosic degeneration can't have influence on dysplasya official result

Many people (not you) don't know very well HD from scientific point wiew, is dangerous to say: "Hereditability of HD: 20% to 40%" is better, and more correct to say: "A dysplasic dog inherits his disease from genetic/hereditary way (100%), but the modulation, expression and seriousness are controlled at 60-80% by environmental factors"

[Juniorwolf]

Today I have been talking with 4 different vets., one of them is Peter Weis which is a specialist in diagnostics and treatment of joint-/bones-illness and radiography (including PennHIP), he is also member of NOVOS(Nordic Veterinary Orthopedics Society).

They all stated that, HD / AD is both EQUALLY a product of enviroment and hereditary, to proove that one of them have a higher % of hereditary than the other is impossible, as you can not create the EXACT same enviroment for two dogs(even harder with more dogs) to grow up in and further more is it impossible two find to dogs with ABSOLUTLY same genes, which in both cases can make all the difference in the final results. None of them have never heard of breeding from ED free dogs, will give almost all puppies free of ED or that breeding from dogs with ED will for sure give all puppies ED, to me they all explained that the hereditary risks of HD and ED is absolutly the same.

Conclution : It makes no sense to exclude dogs with a mild degree of ED and allow dogs with a mild degree of HD, as one is not worser or better than the other.

Was this not the reason why Admin made this step, to remove all dogs with ED ? ...aparrently it is for no reason, unless all dogs with HD is removed too !

Please correct me if I am wrong, nobody is perfect

Rolf

[woland77]

OBJECTIVE: To determine incidence, risk factors, and heritability estimates of hind limb lameness caused by hip dysplasia in a birth cohort of Boxers. ANIMALS: 1733 Boxers from 325 litters. PROCEDURE: Status of Boxers with respect to clinical signs of canine hip dysplasia (cCHD) was registered during an 8-year period. Survival analysis accounted for dogs lost to follow-up. Effective heritability for developing cCHD was estimated by use of a proportional hazard model on the basis of the Weibull distribution. Parametric survival models were developed to identify the influence of potential risk factors. RESULTS: Cumulative hazard rate for cCHD from 7 weeks to 8 years of age was 8.5%. Dogs that were kept on a floor covered with a slippery material were 1.6 times as likely to develop cCHD, compared with dogs kept on a nonslippery floor. Risk of cCHD doubled in dogs from litters with a high preweaning mortality rate. Dogs that were neutered at 6 months prior to a diagnosis of CHD were 1.5 times as likely to develop cCHD, compared with sexually intact dogs. Dogs >5 years of age were 1.8 times as likely to develop cCHD, compared with younger dogs. Estimated effective heritability of cCHD was 0.11. In terms of the risk of cCHD in progeny, mean estimated breeding value (EBV) of the 10 best and 10 worst sires was -0.32 and 0.42, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Registration of Boxers that develop cCHD may provide a strategy for disease prevention. In addition to diagnostic evaluation of radiographs, sire EBVs provide useful information for breeding selection decisions.

Here we describe the method for assessing environmental influence (different environmental influence) in the calculation of genetic value estimate for HD about a population of Boxer. Here i don't read than those (environmental influence) are the cause of HD.
If we want to think to environmental influenc with a practical purpose on CZW we need a similar project. Without this we can think only at phenotype (ufficial result) and genealogical relationship on the selection of stud dog.

[Juniorwolf]

Originally Posted by Navarre

They can be what they want, BUT to be honest there should be some REQUIREMENTS that are the same for all, not changing anytime.

If the requirement (right or wrong) to be in the stud list is the ED 0 exam, every dog without this exam should be removed together with dogs that don't fulfill this requirement.

I fully agree with you ! ...but if this happens the stud list will be VERY VERY small.

Another problem with ED is that ED is a term used for MANY different illnesses in the elbow, which is caused by many different things, on top of that in most countries only one photo is used to decide if the dog have ED or not, if done in a effective way, at least 3 photos is needed and many times ED is given for small things who never will have any impact on the dogs life(movement), all depending on the vets. who decide to give ED or not. The expert(Peter Weis) have just bought a German shepherd himself from one parent with ED 0/1 witch I assume(according to his expertise) he would not have done if it really is so bad as some people here want it to be.

Statistics of HD for the last 30 years show that in general no more or less dogs have better hips than for 30 years ago, despite all efforts to eleminate dogs with HD worser than HD C ....ED have not even been researched as long time as HD, why jumping to any conclutions seems to be a waiste of time and are irrelevant for the health of our breed.

Rolf

[Mikael]

Originally Posted by rolf

Statistics of HD for the last 30 years show that in general no more or less dogs have better hips than for 30 years ago, despite all efforts to eleminate dogs with HD worser than HD C ....ED have not even been researched as long time as HD, why jumping to any conclutions seems to be a waiste of time and are irrelevant for the health of our breed.
Rolf

That is very bad and sad news if it is correct

I think the big step against less HD and ED will come first whit the new DNA testing, but until than I think HD and ED x-rays are to be demands for a studdog.

Best regards / Mikael