Thing is, if that was a mouse that was raised in an enviroment with no contact with other animals, as most mice used for feeding purposes are, it has no clue what a spider is, or what it can do to it. My biology teacher in HS had two snakes in a tank at the back of class. Every other friday, we pushed two of the lab tables together, he put one of his huge snakes on them, and dropped a mouse on the tables. The mouse usually just lwalks around for a few minutes or so, then runs into the snake. Sometimes the snake is hungry, others it is not. To the mouse the snake is could be just a garden hose, its never meet a snake before. It is amazing to watch the snake grab the mouse by the head, and then twist it around, breaking its neck. No venom needed..... The snake then constricts mouse and waits for it to die, then digusts it. Great way to waste 15+ minutes on your last class on a friday.