I think my peas are getting frost bite on their feet. I thought the major requirement to prevent this was blocking the wind. They are locked up in our barn/coop so the wind is most definitely blocked. It hasn't been getting any colder than -5 and even then it's short lived. Still their feet seem to be getting lumpy and when I see them walking they keep lifting them into their bodies. None of the chickens, guineas or ducks are looking like this. Any tips?