Definitely faked.You can see the brown dogs jaws are held shut with a type of band/strap in one of the shots below.In all the other caps the dogs jaws are never open:-
http://home.worldwidedvdforums.com/f...p?f=80&t=16791
EDIT:-The last cap of a muzzle/strap on the white dogs jaws proves the scene is staged & the animals were unhurt.