I’m sorry to hear your sweet duck is sick, are you scheduling an appointment with the Avian vet for Friday and just want to know what to do in the meantime?
I would also add a good liquid vitamin to the water like “ roosterbooster poultry cell” or “nutridrench”
But if she doesn’t like the taste of it and won’t drink the water, you can give her one ML per day of the liquid vitamin with a syringe with no needle attached to following these instructions being careful not to aspirate her
https://www.backyardchickens.com/ar...dications-to-all-poultry-and-waterfowl.73335/
And I would start tube feeding right away because if a duck is not eating at all, they can go down quickly in a few days and might not survive till you get to the vet. Tube feeding sounds difficult and scary but once you try it, you’ll find that It’s not as difficult and scary as you think.
I got a 60 ML syringe and I attached a tube from oxygen machine. I cut it too size and then used a lighter to just carefully warm the end to soften it so there was no sharp edges.Also aquarium tubing is good but you might be able to buy a tube feeding kit that has a tube with it That’s good enough but some of them are a little thin and flimsy, and it’s hard to push the food through it., sometimes It gets stuck and clogged.
I bought some Kaytee baby bird food powder, and mix that with water to a soup consistency and feed 30 ML three times a day . I have also just used my regular duck food, soaked in water and stirred well until it is a soupy liquid. And you can actually add the one ML of vitamin into it once a day if you’re going to be too feeding, he may as well add the vitamins into the food . I will be right back with a video about tube feeding
Me personally cannot afford to take my Ducks to the vet, so I would also be starting a dewormer just to rule out worms being the problem sometimes when they lose a lot of weight like that it’s because they have worms. I would probably use safeguard.