My Doberman sprained her front right shoulder once and our vet recommended this to keep her joints "well oiled".  She exercises hard, between 30 mins to one hour of solid running, wrestling, swimming, or jumping.  This glucosamine supplement is perfect.  Since taking it she hasn't had other sprains or stiffness in her joints.  Tastes like chicken so she looks forward to her daily glucosamine supplement.  Had to give her a high dose per the instructions on the bottle for the first couple of months and then transitioned to the maintenance dose.  It's worked out great.  I hope it keeps her feeling young for many more years to come.