I used to work for a vet and know the different types of stuff. Which is funny because now that I actually own my own kitty, it's like I forgot everything I've learned about cat care while working there. Lol. I do know she eats some of the mice she catches I just don't know how many. I only know of the ones she half eats. Whole or half eaten, a dead mouse is better than a live one slowly destroying my house. And she's very good at she does!