Is this frost bite (pics)?

[sydney13]

A few nights ago it got pretty cold out, -10 degrees or so. I don't have a heater in the coop but it is free of drafts and dampness and I have all cold hardy breeds (except for the silkie), so I thought the birds would be fine. Today I noticed my 2 hens with the largest combs (orpington and barred rock) look like the have frost bite. I have been putting petroleum jelly on everyones combs before the go to bed (Ive heard mixed results wether this really works or not) and when I noticed the frost bite I put on some neosporin.
So here are some pictures of the 2 with frost bite, does it look bad and is their anything I should do?

By the way, they are still laying an egg a day and acting perfectly normal

 

[Fred's Hens]

In the first picture, I'd say, yes, a very slight case. Recovery seems likely.

 

[Miss Lydia]

Looks like it is, just about everyone except lower south has been dealing with frost bite this winter. Me included. Just keep an eye on it for infection, but what will happen is it will turn blk and eventually fall off. You can also put watered down betadine on it once a day let it dry then apply the neo.