Please be aware that the puppy replacement formula can be dangerous as well. We are hand feeding a litter of puppies. They were thriving until we purchased Hartz replacement milk formula. The puppies all got very runny diaharia and one began having seizures and was in so much pain that the vet almost put him down. We finally realized that the puppies began to fail when we starting using this formula – switched back to the vet recommended formula and they are all thriving again! Please be aware that if your puppy is not doing well it could easily be this formula!