I am questioning how much energy is being used up to keep warm, that could otherwise be turned into muscle, when the temp is near freezing.
I don't doubt that my birds can take cold weather, but I wouldn't have wanted them to suffer in the cold as very young chicks when they still needed to be protected and brought down in steps. But still....if they would be in a fairly warm environment, wouldn't they grow faster?
I am not opposed to making an extra tractor for next time I want to raise meat birds, but I am not sure if March thru June wouldn't be better than October thru December.