My bulldog needs to be on a diet. He is short and stocky and weighs 67lbs. He is starting to limp on his right leg and vet recommend that we put him on a diet. He has been on the weight control of Wellness super5 mix, but vet said to put him on a veterinary diet either the Purina OM or the Royal Canin Calorie control(High Fiber or the other choice High Protein). I wasn't too impress with the Purina OM ingredientshttp://purinaveterinarydiets.com/CanineProductDetail.aspx?prod=227
and was leaning toward the Royal Canin Calorie control, now would the high fiber be better or the high protein?