I have 15 chicken and one hen is sick. She retracts her neck, waddles, and butt is lowered to the ground. I see no other symptoms. She does eat and drink. I gave her some bread and she ate it up. The temperatures have been pretty low this winter and currently it is 4 degrees right now. There is no means of heat in the coup we just had shavings and hay the coop is a good size and warmth is the best we can do. What can I do for this hen? We do not have a vet. What should I do? Thank you.