Dysplasia ???????? - Page 5

I see a number of excellent studs in the mid 70's and think even if a bitch is low it is a chance for a next generation thatis equalor even lower. As to the test differences I suppose positioning could be the reason. Thanks for the good info, Jonah

jdh, I agree with your excellent assertion that increases in angulation are not correlated with increased dysplasia. As far as the desirability of using NZ stud dogs for one's bitches, I believe that in general this is not a good idea. However, because the NZ rating can be made at an age as young as one year (it depends when the Xray is submitted for review after the GSD turns one year old), I would not necissarily trust the NZ label at face value. If the dog has some "irreplacably valuable" dominant traits that are extremely desirable, then I would want to have the dog re-xrayed at two plus years old, carefully positioned properly, and then view the xrays myself. I would look at the depth, smoothness and Norberg Angle of the socket and ball, and then attempt to analyze any hip producing records of the dog and his close up ancestors in the pedigree. I would want to find out about the dog's rear upper leg muscle mass (the greater the better), and the overall ligamentation and agility which can be linked to overall joint and muscle health. I think the idea that careful selection for joint health will greatly reduce oeverall health and quality by reducing the genetic diversity available. One can breed to weed out the genes for bad joints (it's polygenic unfortunately, a least 5 genes involved), while selecting and re-aligning the desired genes. These should be considered independent genetic breeding traits. It just takes a long term commitment of the breeder who is willing to start out slow and build quality over time. I know one breeder who culled out bad joints judiciously over a five year period and now just doesn't produce any HD (he only breeds OFA good or or better). He also is careful about diet, avioiding overfeeding, and makes sure that the puppies get enough exercise to be in good condition without overdoing it. There are some breeders on this site who have shown just such a commitment and have attained these desired results over time. These folks also consistently display their commitment to the overall welfare of their dogs in general, are honorable folks in their own right and deserve much credit and praise. I view elbow confirmation as tougher problem to resolve than HD since it may take a minimum of 6-9 months for adequate screening diagnosis and so many things can go wrong (such as un-united anconeal process, differential long bone growth issues and degenerative joint disease (DJD) of the elbow shown by roughness and patchiness of the surface areas which are supposed to be smooth). Special optical filters are needed to see these patches and not too many folks can read these elbow xrays properly (the OFA has these filters and does a very good job in general on elbows--some say they are too tough, but I think they are correct in their pass/no-pass distinction).

Correction. should read: I think the idea that careful selection for joint health will greatly reduce oeverall health and quality by reducing the genetic diversity available is NOT valid.

Good points again Preston, Did you notice a strong genetic correlation on the depth of socket or comparable to that of HD? The breeding of nz stock may be borne out in the legacy of Jeck, but anyone who might have predicted his role in the breed would likely have predicted that the sons and grandsons of Fanto would be the dominant sires of todays Auslese group. As such I find it hard to be satisfied that a sires production capabilities outweigh baggage such as marginal hip status. Also can you elaborate at all on the interaction of (5) known genetic factors to HD?

jdh, we did not notice any correlation between shallow sockets that were round and smooth and later deveopment of HD in specific GSDs. We did find that HD showed up early in young puppies as shallow sockets with flat or deformed heads and laxity in the joint. A knowledgeable vet once told me he though the laxity of HD was caused by fluid build up and pressure in the hip socket due to an inflammatory response (this mushed the bakll outy of the socket). We were fairly certain that shallow hips sockets that are clean at an early age usually stay clean unless the dog is overfed, over exercised or abused in my experience. We suspected that using GSDs with shallow hips for breeding probably resulted in more disabling HD in offspring proportionately than a dog with clean, deep sockets, but can't say for sure since we didn't have a large enough sample to infer properly. When I studied all the available research on the genetics of HD, it appeared that skeletal construction of the hip confirmation and associated ligamentation and muscling was probably determined by a complex interaction between approximately 5 genes, some domiant and some recessive. This polygenic inheritance makes it a somewhat difficult multigenerational task in most cases to produce lines with prodiminantly gopod hips. I agree with you that it is hard to want to use any stud no matter how good if he has unclean hips or a known tendency to produce them. I view clean joints as important as being free of epilepsy, mega-esophagus, megacolonn, bleeding disorders, EPI, and bad temperament. The stud dog that is a top and consistent producer is a rare dog indeed. Some of the studs with good progeny groups also got many of the best bitches early on because their owners breeders were popular and well known. Other dogs could probably do as well or better if given such opportunities.

Thanks Preston, Good info as usual,Jonah

My first bitch (out of an OFA fair and an OFA good) had severely dysplastic hips. While she had a very good life, her painful hips affected her greatly. Due to this, I would not take dysplasia lightly ever. It can be a death sentence for many dogs. On another note, I bred an OFA excellent to an OFA good whose mother was also OFA excellent. Out of five puppies, only one was x-rayed and came back mildly dysplastic.