My 9 month old barred rock, Laverne has one eye closed and is fluffed up and not herself. No nasal discharge, no bubbles on closed eye, no debris in her eye. The eye does look "wet". Her vent area is a little messy. She can stand up, has no interest in treats. She has been vaccinated for mareks, and did not have medicated feed as a chick. What is this, and what is the best course of treatment? I'm borrowing a dog crate in a few hours to isolate her. Thank you!