The first thing I would do is look at your coop set up. Is there a water source in their sleeping area? They will be spending more time in their coop so ensuring that the coop has a low low humidity will prevent frostbite. Take any water sources, add a thick layer of dry bedding, and do not heat your coop. These things can keep your humidity levels lower and prevent frost bite from happening in the first place. For now I'd recommend keeping the area dry, clean, and protected from wind.
Thank you I already addressed these points when I responded to a previous comment. My coop never had water inside and is scooped daily to prevent fecal moisture. It is well ventilated above their heads under the eves.
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Yes, my boy Albert is 1/2 Leghorn and his comb shows it. So far only the very tips have rounded so his comb is still quite sunning. Unfortunately he has lost 2 toe tips to frostbite on one foot. I believe he walked in a puddle outside at some point. He has a funny little limp now but it doesn’t stop him from being a fabulous rooster.( I credit his excellent healing to a compress of comfrey. )
Oh and my girls would wing-flog me if I didn’t let them outside regardless of temperature! The coop is a large walk in with plenty of extra room but they still go outside. They have a large run that I wrap the walls in clear tarps to reduce drafts and blizzard winds so they are just as comfortable out as in.
