Two of my pullets have black spots on their combs. Fish- Easter egger pullet. 5 1/2 months old. Pea comb. A couple small black spots- maybe 5, very tiny. Sesame- New hampshire red pullet. 5 1/2 monts old. A couple small black spots- maybe 3. One or two medium spots. One large spot underneath folded place in comb. I have noticed this for two days. It gets down to about a low of 20 degrees. They spend daytime in the run (hardware cloth) and nighttime in the coop. My dad has put shutters on most of the windows in the coop and plastic over the others, except for the door. They have not been free ranging recently. The coop is a plywood box, elevated, unheated. They just switched to layer pellets. We gave them a heated water dish. The old metal one is still in there. They did not get any treats. Thank you for any advice. EDIT: Sesame also has a small chip out of the end of her beak. She is not affected by it, she still ate the apple with regular vigor. I noticed this today. It is very, very, small. Should I do anything to fix this?