The REAL appreciation comes when you take a few nibbles of the mouse right in front of him to show your approval.
After all, there's no stronger bonding between two living creatures than breaking bread together (or in this case, bones.)
Allow Toothless and Hiccup to show you how it's done:
[video=youtube;Ne6Ss9wiCmI]https://www.youtube.com/watch?v=Ne6Ss9wiCmI[/video]