It would be a good idea to clean up her bum. Offer her some extra calcium and poultry vitamins for a few days.My remaining hen is a 3 year old black decline. She lays eggs regularly - about 5 a week. She doesn’t have lice or mites and she’s been recently dewormed. I don’t see or feel any swelling or bloat, but I could probably miss that unless it was very obvious. To me, she doesn’t look any different than she ever has, except she is a little mopey right now since her coop mate died yesterday.
She has had a soiled butt (I think I saw this as a symptom) for about a month now. She’s also had poor eggshell quality this laying season. I assumed that it was a calcium problem, but now I wonder if it’s fatty liver disease. Her poop was a bit watery today, but it rained and washed away so I can’t get a picture.