hundejager, I would quess a coyote got the cat. If free ranging dogs killed the cat they probably wouldn't eat any of it. Coyotes consider cats a delicacy. The scene of the crime should provide the evidence. There may be tracks, if not other clues can point in the direction of coyote or dog. Most dogs are not efficient killers, and kill for fun. When killing something dogs generally make a mess of things blood, guts,and hair strewn all around and very little if any part of the animals they kill get eaten. Coyotes on the other hand kill for a living and are very good at it. Coyotes rarely leave a mess at a kill, eating what they kill and even licking up the blood. Coyotes can cut up a killed animal into carrying sized pieces as good as you or I could with a knife. As far as leaving the legs that doesn't suprise me, animals seem to like to eat the internal organs first. I would guess that a coyote either got spooked and dropped the hindquarters or you found them before it had time to come back for them.