They said in the article the cat bites the windpipe or spine in the neck.
This isn't always the case as one of my buddies in MT has seen 2 elk killed at seperate times by a cat. Both of them were killed by the cat reaching around the nose while clinging to the side of the neck and it pulled the nose towards itself with one quick motion and broke the elks neck. This happened twice one was a big cow and the other was a spike. Buddy said he wished he would of had a movie camera and filmed it. He said it was really something to see and never would have believed it possible without seeing it himself.
They are killing machines that is for sure.