I have my 3 chickens in there coop with a tarp covering to keep the wind and blowing snow out and a light in the coop for warmth and two of them still got their combs frostbit. One of the combs is white with a black tip and the other a couple of the combs are white with black tips. I will dub them and I will put bag balm or whatever but I would really like the advise. They have gone through 3 winters now but this was the worst so far. They are pets so I don't want them to die, should I take them to the vet?