I am raising ducklings for the first time. I have them in with the chicks. They are all eatting unmedicated chick starter 20% from Tractor Supply. I am not new to raising chickens but I am to ducks. I keep hearing about Niacin for ducks. What is the importance of Niacin? If the ducklings seem to be doing well, healthy, and active 12 day olds would they need it?