Glucosamine is available in a lot of the higher end dog foods. I always feed my dogs the kibble that has glucosamine as a supplement in it, from young up. We used to have a dog that was very arthritic in old age and the vet said it can not hurt. I gave the type in a more concentrated form to that dog, you find it in any drugstore, the one that had the chondrotin as well, not just the sulfate one.
Of course, the human tablet form you are going to have to trick your dog to get them to eat it. Piece of cheese or luncheon meat works like a darn
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