These were made with an iPad app called Echograph. It allows you to freeze certain elements of a video and animated selected portions.
Why, I don't know, but it's a fun toy. Note: if you want to try the app yourself, don't even thnk about using the iPad's camera. You need a rock-solid camera on a tripod.
I have one of the large boar, but he didn't make any motions I could highlight. Five minutes of shooting, and he didn't even twitch an ear.
