My 4 remaining hens are very old.........10 years 8 months. One of them (an easter egger) has white around the tops of her nostrils. I took a better look today, and it looks like the beak substance is wearing away, around both nostrils. I haven't seen anyone picking on her. She doesn't have any drainage and is acting fine (other than she's living with a bad limp). Any ideas what this might be? Thanks.