1 of my hens hatched 5 chicks christmas day... Well today, 2 days later, she's got them outside in lower 40's degree weather, feels alot colder with the wind..... I started letting the hens take care of things a few years ago.. This is the 2nd year in a row we've had a christmas time hatch.. I don't know why 1 of my hens gets broody the first week in december.. Last year it was a different hen... After watching chicks run around in 30-45 degree temps for the last 2 years, I'm convinced that many of the problems (pasty butt, lethargic, etc..) with chicks are caused by them being way to warm.... Last year it kind of worried me seeing them out in the cold, but they feathered out way faster, and I didn't have the integration issues I've had in the past when using a brooder... If at all possible, let your hens take care of your chicks....