What percentage of protein do ducklings need? Do they need a lower/higher amount as they get older or the same amount their whole life? Feed stores around my area only have chicken feed and no waterfowl feed. I had planned on feeding them the same thing I feed my chicks because of this reason. Right now I feed my chicks non-medicated organic starter crumble by MannaPro. It has 19% protein. Will this feed work? Also about brewers yeast and niacin. Do ducklings have to have one or the other or do they only need one if they start to have problems? Also which would be better to give? How much would I give them if they need it?