I'm not sure what Dudley & Sammy would do with a real mouse. But, I do know what they do with a real rat. They look at it, sometimes quickly sniff it, and run down the hall as if a huge beast was chasing them.

They are terrified of the rats when they are running around loose. When they are in the cage, they love to play with them and bat at them through the screen. That is because they know the rats can't do anything to them. When the rats are outside of the cage that is a whole nother story and they would never think about touching one of them.

hehehehehehehehe...chickens.

I can see them killing a mouse, because they are much smaller than the rats and don't look like such a threat to them. Hopefully I will never know....