Based on the picture, should I be feeding a rat pup or rat fuzzy then. I also did a Google search and found the picture I was thinking about on this site and saved it to my computer. Weaned mice are equivalent to rat fuzzy and large mice are a rat pup. If a small mouse is just a little too small for him...should I go for the rat pup and see how he does? Thanks for your replies, I really appreciate all the helpful information!