I do not know what I have done wronge or what I can do to make it better but in the last 2 nights i have lost 3 chickens it has been -20c outside they are inside there coop is 10c there is 40 birds in there. I do not know what to do I got 40 1 to 2 year old chickens in may and I have lost 19 of them now!! please help me