My 20 year old dressage horse in in work giving lunge lessons and is as sound and as fluid as ever. My 21 year old brood mare is out 24/7 and haring round with her 9 month old daughter.
No bute!
Mine's 36 and has Buteless as a rule plus a joint supplement, but does have a sachet of Danilon (he doesn't do Bute!) if the farrier is coming. It puts a right gale up his tail!