I have one pekin that show pretty bad signs of niacin deficiency. There is a total of 4 ducklings. I have one other that shows very very slight signs but this one has issues walk. It has bowed legs and the hips are wide as well. Seems to swim perfectly fine abn eats and drinks well. I started giving everyone 100mg per gal of water which i refill 2 times a day. First question is that to much, second with the worst one recover? They were feed chick starter for a week when i got them. They have been on duck starter ever since.