My duck’s eye looked as bad as your duck’s does for quite awhile before it healed. It was swollen shut and crusted over for at least a week before there was even any hint that her eye might open again. Unless you are confident that what you are seeing is infection and pus pocket, I would be reluctant to mess with it more than necessary. I had to syringe my ducks’ antibiotics into the corner of their bills, one partial drop at a time, crushed and dissolved in water by the vet, so I knew that they were getting as much infection fighting medication as the vet thought was safe, and just wait it out.
I kept putting a moist washcloth on her face and eye every time I handled her. Her bill was nearly ripped off and her whole face was a mess from behind her eyes forward and both eyes were closed over, though one started to open a little after a couple of days. The turning point for her was when after a week or ten days, I gave her swimming water in the bathtub. She was very happy about that and started eating again (after losing a quarter of her weight) and really preening so that she worked the matted stuff off of her face over the next few days. Her worse eye took quite a while to look normal, but she eventually got there.
I’m not saying don’t treat, but to be encouraged and avoid doing anything that could injure a recovering eye if it can be avoided.
Here is Nipper now, five months later. Still a little fragile, but healthy.
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