There is a Barred Owl
around here that might possibly make off with a puppy. It's huge, makes crows look like sparrows. I know this because the crows chase it off when it comes around.
I watched a barred kill a rabbit while out riding trails a few years back. It had a bit of issue carrying the rabbit in flight, but it ended up with a 2-3 pound rabbit 30 or so feet up in a tree.