Some of the chickens with big, single blade combs can get frostbite. I used to try applying Vaseline or Bag Balm to prevent it, but found that when it's -10'F there's really not much you can do. If you see white on the tips, it may turn black. Best to leave it alone. (Touching to apply ointments can cause more pain) The black parts should fall off on their own leaving new pink skin below. The rooster may not lose the entire tip, but usually it's more rounded points.
This guy stood outside in the snow because a little sebright decided she wanted to play in the pine tree. She was sheltered and out of the snow. He was standing guard out in the open. He dipped his wattles in the snow when eating, so they got frostbite too.
Here he is again, standing guard over the little trouble-maker.
10 days later, some of the black began to fall off
About 30 days after frostbite
This guy stood outside in the snow because a little sebright decided she wanted to play in the pine tree. She was sheltered and out of the snow. He was standing guard out in the open. He dipped his wattles in the snow when eating, so they got frostbite too.
Here he is again, standing guard over the little trouble-maker.
10 days later, some of the black began to fall off
About 30 days after frostbite