Ugh, in Erie county, we did get about a foot of snow, with more in the drifts. Made for a fun weekend trying to ice-fish in that mess! BRRRRR. The chickens have been fine so far. I feel bad that they can't (and won't) come out of the coop. I have been throwing corn all over for some fun for them. My rooster was ok until last night - his comb has one point turning black, and his wattles are turning black on the bottom as well. Not sure what we can do for him. His wattles are HUGE, I don't know how he eats with those getting in the way!
First, you need less humidity in the coop.
Apparently there is evidence that vaseline makes frostbite more likely. Maybe it causes more moisture? I forget the “why/how” part.
So, he won’t win any prizes at the fair. All I know you can do at this point is to figure out why it happened. Then change whatever it is about the coop in the spring.
Sorry to hear about your rooster.
Been there with our Marans & Wyandottes, though not so bad with those flatter combs.
Have read/used 'bag balm' it works well, there are also a couple of balms/creams(no water) on the market for protecting animals..dog mushers balms (foot pads).
I have tried the Vaseline, but like chickie-bull said, I had issues with it. Actually made situation worse, and there is not an issue with humidity/drafts in their coop. Only thoughts maybe the comb/wattles had some moisture still on them when I applied the Vaseline & being held in caused it or it was just too dang cold..i don't know
. I haven't used it again and I don't have that issue now, I have used bag balm & when out of that ($), I keep homemade version of dog-foot pad protecting balm/salve.
I try to make a lot of our own products that we use for, well..just about everything.
Not saying to be little miss smarty pants, just saying we can ALL make high quality, less poisonous products for ourselves if we research and take the time to have failures.., but once we find the things that works for us...there is no telling what we can accomplish.
Anyway...Chickie-bull is right, check your moisture level/humidity/drafts...treat affected birds properly..sometimes we do more damage than good in our "caring" methods...try out some products, find the one that works for you & your flock..because some people will swear by this & that, but it only matters what works for you.
Applying whatever your going to use before an issue or extreme cold will be most effective..all of this is just MH&HO. Sorry this got so long winded...
I aaam chickie-bull! I aaam chickie-bull! 
The new nickname has me imagining bunny bums dancing. No idea why.
, just starting to get more than 1 egg every 3-4 days here...would like a dozen before end of the month!!
..you know i am jesting.
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Having them tied out in the nicer weather is chancy, but we are always very near to help deter the wilds.
