I don't know what to look for exactly. AT FIRST, would it be white? black? swollen only? purple? Would it turn black later? I'm sorry, but I did a search and didn't see anything. It is in the negatives F here. My orps are out of the wind, and are staying dry. I applied udder balm 2 days ago in preparation for the arctic cold snap. The tips appear white on a few of the girls. I'm not sure what I should be looking for. Thanks for your help. Please post pictures if you have any to help illustrate!