I had six horses in the North pasture. When I was out in the yard I heard a commotion, look up and a big dog was chasing them. The dog ran them into a corner and they turned and ran back across the pasture as I ran toward them yelling, get out of there. The horses stopped, looked at me for a coupla seconds and turned on the dog. They ran it across the pasture twice and the dog then dove into the electric fence between the wires. With a loud yip it ran out of sight. Never saw that dog before or after. The horses were running in fear until they knew I was near and the fear left them. When I fall in the pasture I have two that will come up to me so I can use them to pull myself up. No teaching involved just trust and instink.