"I give THE MISSING LINK to all of my animals, and I swear by the product; however, if your dog is under 5 years of age, please do not use the PLUS formula. The following is directly from the FAQs page from DESIGNING HEALTH, the makers of THE MISSING LINK.
"Most usually, depending upon the breed of dog and other extenuating circumstances that may exist, it is not advisable to start a dog on the Missing Link Canine PLUS Formula with glucosamine until they are at least five years old."
The glucosamine supports health in aging joints, and supplemental glucosamine may help to rebuild cartilage and treat arthritis. This supplement is not needed in young and developing puppies, and dogs in their prime."