Of course, kitteh can't bring down a cow. So she'd have to catch the cow unaware, bite off a piece, and run away before the cow stomped her.
Sound unlikely? Cats haven't figured this out yet, but there's a shark that operates like this, the cookie-cutter shark, Isistius brasiliensis. Because its teeth leave a circular hole, as if cut by a cookie cutter, in the flesh of a much larger fish, shark, or whale. The cookie-cutter shark sinks its teeth into its prey, spins around to make the cut, and then swims away to dine. Details here. Be sure to check out the links at the bottom, pictures of other fish and cetaceans missing cookies.
I hadn't heard of the cookie-cutter shark before running into a mention of it on Cheryl Klein's blog. (ObFictionWriting: C. Klein is a YA editor.)
The process strikes me weird and creepy, in a way that normal predation doesn't. But when you think about it, in the human world, snapping off a bite but leaving your prey alive to be bitten again at a future date is probably more the rule than the exception. That's what mugging is, after all. And day-trading. And personal injury litigation. And taxation.