My mastiffs guard our coop. They have killed 3 cats, a hawk and a skunk (ohhhh so smelly) who were to close or trying to get into our coop. They caught one of the cats with it's leg in the coop trying to grab a hen, who was to curious/stupid to stay out of the cats reach. I have pictures of one of them guarding the a cage with our latest batch of broilers in it. I still have 3 of those broilers and one always sleeps with it's head or legs out of the cage and they just sniff it and move on to check the other animals. They "play" with the horses and guard the rabbits and chickens.