About three weeks ago I noticed one of my 6 month old RIR hens was looking funny. Her tail feathers were a mess and she was walking weird. She started to not be able to get up from the ground and would flap her wings and scoot backwards until she ran into something and then use it to help her stand. She seems to have trouble going from standing to sitting and vice versa. She spends most of the day laying in the run. I have called all the vets in my area and none see chickens. I called the feed shop where we got her and they suggest coccidiosis and we ran tiramissin. No change. We called Ohio State poultry science dept and they thought ricketts. We have been supplementing the water for the past week with vitamins and electrolytes and no change. Her color is good. She is eating and drinking and her stool is firm. She is still laying. She just seems to have really weak legs. When she flaps her wings they are in unison. Does anyone have any thoughts?