Puppies who are still growing will need a food higher in calories, vitamins, protein and minerals. If your puppy shows sign of digestion problems like diarrhea, constipation or vomiting, it is best to seek advice from a vet. The vet will be able to determine if your dog is sick or if his diet should be changed.
A responsible dog breeder should give you proper advice on your puppy nutrition, having already fed the litter with puppy food. As long as your dog will be considered a puppy, you will have to keep him on the same puppy diet. Once an adult, you will have to change gradually your puppy nutrition. To do so, simply mix his puppy food with his new dog food. Feeding an adult dog with puppy food for too long can make him become overweight as puppy food has a higher level of calories than adult food.