Do Cats Eat Mice After They Kill Them. Most cats do not eat mice. Cats also consume prey to get taurine, an essential amino acid.
They usually do the same with mice and birds, although one cat i knew took birds apart before leaving them. Kittens can be taught to hunt mice, but the natural inclination of house cats to actually kill is diminished. If you can't set the mouse free on your own have someone else do it for ya but your cats will be a lot safer.
I think it is just the cats' nature to hunt and if they have chance to eat one then they will.
Your cats are 'doing their job' and 'earning their keep'. However, many cats don't eat their prey, and sometimes they don't even kill it. Does that mean every cat who catches a mouse will eat it? That looks like some sort of rodent.