Are My Chicks Starting To Get Frostbite?

[bacibeau]

Hey everyone!! I have two buff orps and three speckled sussex that are about 7 months old now all pullets. Temperatures around here have been getting as low as 29F at night. They sleep in a coop with the door shut, a little window screen to ventilate, and no heat source. We loaded the coop floor up with wood chips to try and give them as much heat as possible. They’ve still been playing around outside all day like normal and only go inside to lay their eggs. They seem to be eating their regular food and all of them attack any lettuce or apples we give them. I just started to notice however that some of their combs and wattles have started getting white spots on them and some of the edges have some black on them. I’m hoping it’s just their normal color and some dirt but I just want to make sure that they aren’t starting to get frostbite. I also read that it could be a fungus but I’m not really sure how to identify either.

Any advice you could offer is much appreciated!!

Here are some pics (they aren’t grouped in any particular order):

 

[Wyorp Rock]

I’m hoping it’s just their normal color and some dirt

Have you tried wiping it off to see if it's dirt?

I don't see anything concerning. Maybe a peck scab or dirt.

Good ventilation and low moisture in the coop is a very good way to help prevent frostbite.
Here's good info on frostbite and how to prevent it.
https://the-chicken-chick.com/frostbit-in-backyard-chickens-causes/