https://www.backyardchickens.com/threads/runner-duck-cough-or-hiccups-aspergillosis.1606047/
So that’s all about what I went through with my runner duck.
Majestic waterfall sanctuary also recommends the oxine AH nebulizer treatments
If you click on aspergillosis in the diagnostic chart, it takes you to an article about how to use the oxine
Is there any way you can take your duck to a vet?
Another question is do you ever use straw and have you ever used any of that? Maybe smelled a little bit musty?