I just learned about this last week; was reading about putting either a donkey or llama out with a flock of sheep to protect them. Interesting.
Either one will lay a serious hurting on coyotes. The neighbors in back of me have a donkey in with theirs, on rare occasion I hear him raising heck in the middle of the night. No doubt that’s him and a coyote.
One of my neighbors has a herd of alpacas with one llama. Couple of times a year the llama stomps a yote into a pancake.