We always recommend starting with a single protein during the transition to Viva. The best protein to start with is the one that's in their current food right now (for example, chicken & turkey are popular options!). You can introduce other proteins after they transition well—we always recommend a slow introduction even if it's a protein they've had previously with another brand! For more information about transitioning to raw, visit our guide. After you are fully transitioned, we always recommend rotating as many proteins as your pet tolerates / does well with (3-5 is great!).