Can I mix puppy food with adult or all life stages food for my dog?

Hello and thank you for reaching out to Petco Pet Education Center, formerly Petcoach. A pug that is younger than 6 months should eat a puppy diet to help her grow and get the adequate nutrients and vitamins she needs. Puppies and adult dogs have very different requirements in terms of calories, calcium, phosphorous, and other nutrients. As she gets older, ie in the 6-12 month range, it is OK to start mixing in an adult or all-life stages diet in with her food. Just be sure the total amount she is supposed to be eating based on what the bag says is appropriate. Eventually, once she is about 12 months, she should be on an adult dog food, for maintenance. I recommend consulting with Beanie's regular veterinarian to see what specific types of food they recommend for her! Top dog food brands include Purina, Hills Science Diet, and Royal Canin. Beanie should NOT eat a grain-free, vegetarian, or vegan diet, as these are linked with dangerous heart conditions and other growth related diseases. I hope this is helpful!