Yesterday I came back from vacation and noticed my 5-year-old Cochin hen has swelling in the fleshy part around both her eyes. She has plenty of energy and a hearty appetite, but it seems to be slightly impacting her vision- she got a corn cob yesterday and pecked beside it a few times when she was trying to take a bite of it. It doesn't seem to be causing her any pain and otherwise she is perfectly healthy, but I'm wondering if anyone knows what is causing the swelling and how I can treat it. There is no discharge or abnormal fluids coming from her eyes.