Hey everyone! I'm from beaver county Pennsylvania and I have 5 chickens. 2 red pullets and 3 white. I've become concerned with one of my whites. Her comb is looking dry, feeling hard, and turning white. I put petroleum jelly on it today hoping it may help. Any advice? It's been very cold lately so we have confined them and put an addition on the coup and added a heat lamp. I have a picture I will try to post. Thanks everyone!