Can you feed a 3 week old puppy its mothers milk AND formulated at the same time?

It is recommended to feed a 3 week old puppy only its mother's milk. At this age, the puppy's digestive system is still developing and may not be able to properly digest the formula. Additionally, the formula may contain ingredients that can be harmful to the puppy. If the mother is unable to produce enough milk, it is best to consult a veterinarian for the best course of action.