[cejx]

One of my exbats has a bright red bum.  She never regained her feathers around that region - whereas the others fluffed up nicely. I've checked her for mites, she's laying fine and seems as daft as ever.  Is this something I should be concerned with?  She would be about 2.5years.

[CluckyChicken]

My light sussex is the same.  Now about a year and a half, never moulted but lost her feathers on her bum and they never regrew!  Hopefully someone will know 

[Helenaj]

Don't worry - hen's flesh turns bright red in sunlight - it's just the way they are. If you can't see any soreness it's perfectly normal.