Sorry to bother you, but I have been looking desperately to find out what is wrong with my hen. Since you are obviously very knowledgeable, could you check out this thread and see if you might have any idea what the problem is? Thank you.
https://www.backyardchickens.com/threads/pale-comb-no-interest-in-food-and-diarrhea-please-help.1313078/
https://www.backyardchickens.com/threads/pale-comb-no-interest-in-food-and-diarrhea-please-help.1313078/