You got great advice
I just want to add you may not see improvements for 1-2 weeks
Please don’t give up
Keep giving the durvet vitamin B complex and continue for a week after she has fully recovered
The nutritional yeast I do with all my newborns till 10-12 weeks at 1 tbs to1 cup feed after that I sprinkle it on my adults feed a few times a week and in winter more often
Chicken feed doesn’t provide enough niacin for most ducks and some ducks just need more then others even if they are siblings
Keep the B complex in the fridge as it keeps for a long time this way
Also if using chicken feed by 3 weeks I stop with starter and have them on grower / finisher
I made the mistake my first round of ducks and kept on starter till 7-8 weeks and my little khaki Campbell lives with one angel wing ( vets said it was my high protein feed for to long )
Since then I switched and have never had the issue again and raised many ducklings and currently have 19 ducks ages 2.5 years to 9 weeks
He is father / grandpa to well over 70 so it’s not in his genes ( as some angel wing can be )
I also stay with grower even with my adults as I have both male and female
My calcium is crushed oyster shells in a side dish for my girls
Good luck
And keep us posted on her recovery