We just took one out on our farm. It had one of the horses pinned up against a fence and he was attacking his face. It's one of the same dogs I had run off the big deer I eventually killed. Had a neighbor kill a good 9pt yesterday and his nose was bit off and had become infected. I'm pretty sure the way this dog was after the horse it was the same one that went after that 9pt. We have 2 left to go. If they don't have a collar on then get rid of them ASAP!
I hunted a property with a few feral dogs. They were very aggressive to everything. One got too close to me, growling. That was his last day. Haven't seen any at all on any property I hunt in quite a while.
I had a coon hound chasing everything that moved on an adjacent property. So long as they stay over there I'm fine. If he crosses the fence and chases deer on my place you may need to buy a new coon hound.