We discovered this evening one of our laying hens, a 7 month old Buff Orpington hen, has a horrid, red mass haging out her back end. It is dripping moisture and poop. The size of the mass is a little bigger than a golf ball and is bright red. Her feathers around her vent and belly are fouled with the moisture and poop. The is a slight foul odor but is not a poop odor. Her crop is empty so she hasn't been eating but she gets around with the other hens. The other hens have not been pecking at her, thankfully. It does not appear to be an injury from a predator, etc., as there is no external tears, blood, scabbing, etc. elsewhere on her body. She's not fluffed up and droopy like she's sickly. I don't know if she has layed an egg lately. All 8 of my laying hens share 2 nesting boxes (by choice--they have 9 to choose from) and I'm not home in the daytime to watch the hens lay eggs. That said, we haven't had any "double yolkers" or exceptionally large eggs for over a week. I have the poor hen isolated in a large dog crate. The floor is cardboard lined and I didn't put any bedding her crate so as not to contaminate or damage whatever is hanging out her back end. She has water but no feed. What do you think it is? If it is a prolapse how do I treat it? What if there's an egg stuck in there inside that horrid mass? Thank you for your help. I haven't had any serious injury or health issues in the short time I've had chickens.