This is our 4 month old Barred Rock chicken. We have had her for about a month, we got her from a feed mill store and they say she is vaccinated for Marek's. About a week ago I found her in the chicken pen unable to stand or walk. She is housed with 2 other 4 month old chickens. Her poops seem normal and she is eating and drinking. She is thin. We are putting vitamins and electrolytes in her water. She is on medicated chick feed, no other food. She can move her legs but just can't seem to get them in the right position under her to stand. Legs also seem too weak to support her. Nothing seems wrong with her respiratory system and she seems OK in every other way. The vets here don't really seem to know much about chickens, so I am trying to get some answers/advice here. Also what do you think of her sling set up? I take her out of it at night or when I am not home. She then just lays on the floor of the cage, she does seem to try to get up and stand when she is out of the sling and on the floor...just can't seem to be able to do it. The floor has a rough wood surface so I don't think it is too slippery. I put her outside on nice days, seems to perk her up. Any thoughts advice is appreciated! Anything additional that I can do? What do you think is the problem? Hasn't really changed much over the last week except does seem a bit stronger.