..we have some worthless dogs but i'm thinking about getting some guinea fowl to protect us from ticks and to scream at strangers.. does that count?

i do hear that geese are pretty hard core for protecting themselves, don't know about other animals..
but seriously, a relative breeds the great pyranees, and they are everything people say. plus they look like sweet huge polar bears with black noses.
we have a border collie who has FAILED to keep rabbits from eating garden lettuce.
we have as predators: neighboring dogs that people aren't responsible enough to fence, black buzzards (the horror) and birds of prey (which i don't really count as bad) snakes to threaten our rabbits, (ditto), our own dogs to threaten the rabbits, hopefully nothing to bother the cows, working on getting chickens...
we haven't really gotten a guardian animal yet. if one of the dogs in an aged state leaves this world, i'm going to lobby for a pyranees or a german shepherd.. i had a shepherd when i was a kid and they are wonderful.