
FWIW, it was -24F where I live last night. This morning, it was only -14F when I went out to check on the chickens. I did not open the pop door because of the cold and blowing wind. My chickens don't want to go outside in cold temps like this anyway. However, I have both feed and water inside my coop 24/7, which I check every day. Also, I check on the eggs twice, or even 3X per day when it gets this cold because the eggs will freeze and crack if not taken into the house.
I hope your chickens bounce back fast under your care. Glad to hear none died while you were away. I think your chickens will be able to recover from any stress they had to endure while you were away. It could have been a lot worse.