My 7 1/2 month white leghorn hen is not acting like her normal self. Yesterday she was taking a dustbath but did not look too well. I walked up and petted her gently, which was worrying because she never lets anyone get within a few feet from her. She was scared for sure, so I let her go. She walked a little ways away and sank down again. I approached her and she walked off to be with the other chickens, who were by a big puddle formed by the hose, which we have to keep on all night to prevent it from freezing. This morning, she was fluffed up in the shade (and it is cold out too) with a floppy comb. Her comb is always flopped over a little, but today it really didn't look good. She does not want to eat but she did drink a lot. Later this morning she was running around with all the other chickens, but soon resumed her listless state. My biggest concerns are a disease, (There are a lot of white-winged doves, mourning doves, grackles, and cow birds visiting the coop), or something picked up from the puddle (we put a bag of beet pulp out so they could eat the bugs, and then it was soaked by the hose), or poisonous plants (she was in a farmer's field yesterday with some nightshade, and there are oleanders by our property). Now an 8 month americuana seems to be showing the slight symptoms that the leghorn has. She fluffs up her feathers and stands on one leg for a few minutes. Does anyone have any ideas on what all this could be? I'm really worried, and this is my first experience as a chicken owner with any sickness.