U of Penn researcher's along with some local NJ-PA DE trainers /breeders have decided that even quality kibble of the PUPPIE variety promotes to much fast growth in large breed puppies, that later in life causes joint and arthritis, they are promoting feeding adult food, and interesting enough even though the pups fed puppy kibble grew larger at 12 months the other littermates achieved the same size appx 3 months later and at 20 months the dogs were within 2-7lbs (some of each food group were larger) The puppy fed group all showed some joint issues as early as 18 months and arthritis was found in 62% of puppy group and only 28% of adult food, as always more test are running now.