My chicken Ella Sue, will not walk. When I first saw her this morning she looked like she was taking a dirt bath. She was lying on her side just sitting there. When I was tossing them their morning treat, she did not move and take her position as top hen. When she finally did get up, she collapsed. I've moved her into her own pen and gave her some food and water where she does not have to move. She's eating and drinking just fine. What do I do???