I walked outside to feed this morning and noticed my Brown Leghorn standing alone in a corner, all puffed up with her eyes closed. I picked her up (without a fight, which is a bad sign) and carried her in. She is very skinny, so she hasn't been eating much. I started her on Tylan 50 immediately but she's not doing well. What can I do? Any ideas? I'll try to get some food and electrolytes into her. Should I put a heat lamp in her cage? She's fully grown, but she's very cold.