Yesterday, the hen stopped out over night and when she returned in the morning she was in a significantly poor condition.
When I went up to the farm, she didn’t mind me picking her up and her head flopped into my arms. She didn’t make any noise but repeatedly open and close her mouth as if she was trying to eat (her food and water bowls were full so I suspect she has been unable to eat or drink).
‘Swollen Eyes, Open mouth breathing, Bubbles in the corners of the eyes, Pale face, Sneezing and coughing and gasping ,Runny nose, Loss of appetite and not drinking water.’ (http://www.backyardchickens.com/t/668326/infectious-coryza-and-chickens-its-like-a-severe-cold)
The bacterium survives 2-3 days outside the bird but is easily killed by heat, drying and disinfectants. Intercurrent respiratory viral and bacterial infections are predisposing factors.
Medication with a sulfonamide or antibiotic is recommended, however this requires a vet to prescribe the medication. But I can bathe and treat her eyes…
I’ve seen that washing them with saline solution and using colloidal silver eye drops should help but I’ll continue to research!