I live in NE North Dakota, and the temperatures have been bitterly cold. The coop average has been about 10 on warm days and below zero on colder days. All of the chickens have been ok besides having cold feet. My 10 month old cochin roosters have terrible frostbite on the tops of their combs. It started just on the tips and I would rub the tips when I was out there and it seemed to be ok, but now its going down toward their heads and its black. Is there anything I can do or put on the combs to keep them from freezing? I show my chickens so I would like to save as much of their combs as possible. Any ideas appreciated!!