I have a Langshan pullet that hatched from straight-feathered parents, with only straight-feathered parents in the line. Thing is...her feathers are curling. Another member told me it was from a vitamin deficiency but couldn't recall which one. I looked in my manual and can't find anything about vitamins affecting curling. I wish the camera did it justice. It is literally like the feathers on her shoulders and secondaries are curling forwards towards her head, and her primaries are curving in towards her body. If it is a vitamin deficiency, why are none of the other chicks experiencing it?