That's what i remember! My Limpy gobbled down a portion of "niacined" meal worms in the summer that was meant for three to four ducks and he is still alive and - limping…
Non medicated is what Ducklings need. This niacin need is not exactly true. I raise calls without any added niacin and no issues. It's a lack in proper diet. I feed all my Ducklings peas and Romain Lettuce too from about 5 days old. Selenium is also needed through the proper balanced diet.
Most of the time proper feed has all they will need but every once in a while there will be a duckling who needs a little extra help that’s when supplements come in. Not everyone can get just the right proportions that ducklings need and have to feed chick feed which doesn’t have the right amount of niacin so having some form of niacin in hand is always a good idea.Metzers who is a reputable breeder here in the USA and you can pull up their web site and read how important niacin is to waterfowl. And what can happen if they don’t get proper amounts.