Rufus eats rat

Last night I was talking to my neighbour, Sue on the front porch when I heard a howling sound.  It was Rufus notifying me about the rat.  She disappeared and later I found her in the kitchen with just the tail hanging out or her mouth, crunching away.  Yuck!  How do they eat them like that?  They're all sick.  I had to go and and when I returned, there was a rat-mask waiting for me next to her bowl.