two of my hens appear to have some yellow in their combs - i searched through the forum and it seems like a small bit of frostbite. if it is just yellow on some of the comb, does it make sense to dub it? i don't want them to get an infection, but i'm worried about making a mess trying to dub them! since it's only the end of january, and we still have at least a month left of winter, with cold temps, i suppose they could still be at risk.