well the will smell the food, move closer to it and then it will pick it up with their paws, just like us , the rat will take a bite out of it and then chew. Once it is all chewed up they will swallow it.
Not before the rat eats the mouse.
Owls
It depends on what the rat eats. if it eats noting but cheese, it will gain between 10-15 lbs.
rats
No, the giant kangaroo rat eats grass and seeds.
a black rat
Kit fox
it eats it.
Sure. My rat eats smarties as treats.
yes
Predator-Prey relationship
none unless in the near by future than no