When it comes to taking care of a new puppy's nutritional needs, you'll need to take up where its mother left off. She will be a tough act to follow During the first two days of its life, she provided powerful antibodies in her colostrum, the highly nutritional fluid she produced until her milk came in. After that, her milk met your pup's nutritional needs. The job of meeting your puppy's nutritional requirements is now up to you. If yours is an adult small dog, its dietary needs differ greatly from those of a puppy, but providing the proper nutrition is still vital to how it looks and feels.