2 days ago my husband noticed one of our chickens was just sitting in the corner - we have brought her inside and isolated her - she seems to lean to one side, the leg that she leans to is fine, but the other foot is all curled up. She hasn't eaten much, her poop is yellow. We have been syringe feeding her some electrolytes in water. We really expected her to die over night but this is now day 3 and she's holding on - not getting worse - she is a bit perkier and fights the syringe - but not really much improvement. She won't stand up on her legs. We have had her about 6/7 years. It's winter here in Australia - but has been wet lately so the pen is a bit muddy. Suggestions on what to do?