My BP has ate four mice with no problems. Two weeks I tried to give him a rat pup but he didn't even look at it. I left him alone for a week then tried again last night and no luck. He is acting a lot different the the rat pups than he does with the mice. He goes after the mice right away. With the rats, it's almost like he is going up to them to smell them. I have put the rat in mice a bedding overnight to try and get the smell on the rat but no luck. Any idead on what I can do now?