Bag Balm and neosporin will work (pine tar will, 99% of the time, keep them from repeating), but to prevent this happening often get something that tastes bad - pine tar/masks injury (like blu-kote).
We keep a 15w incandescent in a securely fastened shop lamp fixture aimed up at the inside of the roof. This provides just enough light to see, but keeps them calm. It was -4°F here this morning and, though most don't want to come out (one BSL hen joined the turks outside), all are in good shape.