feline enemies

Most of all cats love mice. The hunting instinct is inborn. Even when you regularly feed your cats, it will not pass up an opportunity to chase after any mouse that crosses its path.
Cats love to chase (and sometimes kill) mice. That's a given, and something that most people do not find too alarming. In fact, people in many countries still utilize "barn cats" to dispatch unwanted rodents - a win-win situation for all parties (except the rodents). The cats have plenty of food available, and the farmer is assured of grain bins undisturbed by hungry mice. A perfect scenario, eh?
Almost. In addition to barn cats, many suburban indoor-outdoor kitties will occasionally bring home a small kill to proudly display, which we humans (depending on our constitutions) might or might not allow him to eat. If not, we might be tempted to just pick it up by the tail and dispose of it in the trash container, or down the toilet. The problem is that, depending on the region, those little mice may be loaded with a variety of "nasties," that neither you nor your cats want to encounter.