The temps have dropped, and from what i've read here, we keep no heat in the coop. They are opened in the morning then closed at night. The temp today is 10 degrees. I noticed they BOTH dropped weight when it first got cold, but one has bounced back, the other is kind of skinny. She tends to keep in the coop while the other one goes outside every once & again. She is not sick looking, just thin. Does anyone know why this could be?