I have had my long time vet and then two ortho vets tell me that there is absolutely no conclusive data that show that glucosomine effects any changes in joint health for dogs or humans. On the other hand, if the owners believe it helps and then keep the dogs well exercised, lean and fit it absolutely does no harm. The ortho guy said almost the same about adequan, but I have stuck with it for 3 years on a dog with a bad hip xray. Maybe he would be fine without it, but I'm not going to risk taking it away now!;-)
I understand that some folks swear by it and I am not challenging anyone. Just repeating what I was told.
I have heard the same (ie, no conclusive evidence that it works) and yet my 88-yr old mother has been told to take it for her bad knees by both her main physicians. And I do know people that are sure it helps their dogs. From what I have heard it can serve both preventative and restorative purposes.
Both- but there's a big caveat to the actual effectiveness with glucosamine-chondroitin supplements. Glucosamines are a group of compounds that taken individually have widely varying effects. Some are utilized developmentally in building articular cartilage and sinovial joint capsule, but do nothing in adult dogs. Similar compounds have been shown to promote joint regeneration in adults, but are very sensitive to processing (must be cold processed). Further, some compounds that classify as glucosamines have no effect whatsoever, and even of those that have, few have had their effects adequately studied in dogs.
The point is, supplements and foods with glucosamine don't usually tell you which molecular compounds are being used, where they originated, what is the concentration or how they were processed. While I don't think they're detrimental, I think you can end up paying for a lot of snake oil and potentially relying on something that is providing no benefit.
It seems like Fish Oil has a better tract record, at least with humans than Glucosamine as far as it's use and effectiveness. No? Seems like it would have similar effective results on dogs too. Just thinking out loud.
M knowledge of it comes from high performance horses not dogs, but there is extensive research, like radioisotope tests, supporting very good effects from injecting the correct molecular weight of glucosamine or chondroitin sulfates. You can read up on Adequan or Legend- brand names of the injectables. I know that human and equine studies of the oral supplements have shown very little is absorbed through the digestive tract, I'd assume dogs have similar results.
I've had horses and dogs both on Adequan with pretty amazing results.