my ducks are sick and skinny what do I do i think it is the feed I put vinegar in there water I heard it helps
This gives us little no information to even suggest what you might do. More information about the birds and your setup needs to be described. In addition to the other questions asked-
Define "sick", how are the birds acting that puts them off as sick to you?
Do they look skinny, or have you tried weighing the birds and comparing them to breed weight tables online? How does their keel bone feel?
Could you post a few pictures of the ducks?