Puppies can transition to raw immediately since their digestive system is still in good shape. Older dogs that have been fed kibble for a long time may have a harder time transitioning. Most older dogs and cats have been fed sterile (cooked) foods most of their lives, so we recommend a raw pet food diet be introduced slowly over the first week or so, mixing some in with their dry food to start is fine. Green tripe is a great way to build up the healthy gut bacteria. Raw food can be increased to 2 to 4 percent of body weight depending on activity level as well as dietary goals.