So far no loses from the cold at my house. I did loose a quail that was egg bound. My young bantam RIR's and Silkies are still sleeping in the grow out coop at night but hang out with the big girls under the main coop during the day. They have been joined by my 2 year old Silkie "Apricot" in the grow out coop at night, their mom Momo gave them the boot and is sleeping in the main big coop with the Rusty's flock. My new mom and chicks are doing great. She was a little upset yesterday when the water was froze. I checked on her and the chicks yesterday and noticed the water was freezing up. I screwed the glass jar of off the water base and set it aside so i could clean her little coop and give them some food, and she came right up to the jar and started pecking the glass all over as if to say, "Look at this, you had better get this fixed right now because my chicks need fresh water!". I moved one of the lights closer to the water jar and so far no ice. I get a little nervous letting hens hatch chicks during the winter after last year's deaths. Checked on the mom a little bit ago and it was still 40 degree inside her coop. As long as they make it through the first week and they have daytime temps inside the coop during the day of 60 degree they will be fine. The coop gets warm during the day due to its a-frame shape and black shingles. It is supposed to be -5 in Lehi tomorrow night so i will spread a little more straw out in the coops and adjust some heat lights to help. Keeping my fingers crossed.