nom nom nom wut?
It's a deer leg. He wasn't the only one picking at it. ;3 The puppy had already had his way with it, so some of the cats moved in for a share.
Sure, they tear it up. See his right front paw there in the photo? He was trying to hold the leg down while he yanked on the meat. Wasn't too effective though, it'd still come up off the floor a little.
He would dig his front teeth into an attached chunk of meat and pull it up, then put it in the side of his mouth and crunch it off with his back teeth on that side. Kitties can't move their jaw side to side, so that's standard operating procedure. :3 Cuts right through all that sinew.
Link
Fulgens
That looks like too much heart for one kitty.