Think for a moment about what cats like to eat. If they could hunt down, catch, and eat one thing, what would it be? That’s right: mice. Cats hunting down mice is so common that it’s become a figure of speech. So this raises the question: Why aren’t we feeding cats mouse-flavored cat food?
The world is full of unwanted mice, so why aren’t they put to good use by being ground up into cat food? Why, instead, are we serving our cats Natural Wild Alaskan Salmon & White Meat Chicken Entrée in a Delicate Broth? Do cats really care if the broth is delicate, or if the tuna is albacore or skipjack? No, of course not! They’re predators!
The most obvious reason why cat food isn’t made out of mice is because it's not cats who buy cat food — it's humans. Humans want to think that they’re feeding their beloved kitty the best cat food imaginable, and the more gourmet-sounding, the better.
Another reason is psychological. When we open up a can of cat food, the smell needs to be, if not pleasant, at least decent enough to justify serving it to our furry friend. I have a hunch that ground up mouse doesn’t exactly smell very good, and if it did, we’d probably find it incredibly strange that the smell of mincemouse is appealing to us.
The final reason (and probably the most important) is logistics. Mice are really small, and only weigh about two-thirds of an ounce. This means that you’d need about four mice to fill up one standard can of cat food, or more than 100 mice for every 24-can case. If a cat food company decided to take this route, they’d need to raise millions of mice, indoors, and find a way to humanely slaughter them. And because it’s not exactly easily to get the meat off of the little rodents, your cat would end up eating a lot of fur and bones.
So on second thought, it’s a lot easier to just keep using leftover scraps and byproducts from slaughterhouses and fish processing plants.