Does anyone know where I can get a safe list of foods for ducks? I have 10 runner ducklings and I would like to know what are good supplement foods for them. I am feeding chick starter now and I just gave them some oatmeal with some clover mixed in and they loved it. I know they need extra niacin but I cannot find brewer's yeast anywhere. What else can I use to get them extra niacin?