We have heaters in their water tanks and so far no ice thankfully. Its hard to believe they can stand such outside temperatures. As long as you keep them fed well, they make it. My wife use to train horses in this kind of weather. They would put plastic between the barns at Keeneland to break the wind and ride the horses. I have seen her come in from the track with ice frozen on her face and gloves. I don't know how people work out in this kind of weather. That was years ago. The cattle people are having a hard time right now keeping their newborn calves alive. This will hurt their bottom line for sure this year. I am just looking forward to some warm weather and some sunny days on the lake. I pray everyone stays warm and fed during this cold weather.