I had switched from Purina Adult Food to Nutro Large Breed Adult Food. I had switched because I wanted my dogs to get the glucosamine and chondrotin. Kilo (rotty) had developed arthritis pretty young. I fed him Purina Dog Chow. I either didn't know about the Large Breed Dog food or they didn't have it. I can't help but wonder if it would have made a difference if I had fed him the LB food. It can't hurt to try it. Let us know what you decide.