I am a new chicken mother and have only 9 hens. 3 are white leghorns. One of my leghorns doesn't look good at all. Head looks sort of like she rubbed it in old oil and her comb is very pale and limp (to the point of being flat). Her feathers look ruffled on her head and shoulders. We've had temps down to 12* and they are in an unheated coop - but all the others look fine. Does anybody have a clue about what's up with this one hen?