Yesterday we found one of our ~4 week old buff orpington hens with her head almost completely between her legs and unable to walk forward at all-- whenever she tried to move, she'd end up walking backwards. There was no sign of an injury or anything, and all 10 of the rest of the flock are absolutely fine. We have been giving vitamin E, selenium, liquid bird vitamins and prednisone, which may be helping a little bit, and it's eating fine, but we just wanted to check if anyone had any idea what this could be. Do Orpingtons have the same crested head problem as bantams that make them vulnerable to brain injuries? Does it make sense for this just to be a deficiency when no other chicks have this problem? Could it be a more serious infection?