What do I do with a frostbitten comb?

[sleepyt]

My chicken's comb is all white on the top and so I think it is frostbitten. It got to be around minus 8 celcius today but the chickens still wanted to go so I let them out of the coop. Can i keep the chickens inside the coop for the whole winter?

thanks,

Tia

 

[SandyK]

I think we are supposed to put a thin coat of Vaseline on the comb when it's going to be really cold. Not sure on what after though.