If I was in your situation, I would get a Great Pyranees or GP mix, to live with the goats. Llamas and Alpacas are great guardians, but they need a barn where they can herd the goats into and block the entrance to be really, really effective. Getting a big herd of goats gathered and ushered into a structure is not always an option when you have packs of coyotes roaming, or loose dogs.