ksmith, I know I am new here, but I hope I can help. I had the same question, with the feed, but I had already been feeding mine Purina Medicated Chick Starter because it is what the feed store, where I bought the ducks, told me to feed them. Then I ran across something online that said it would kill them.
Needless to say, I began flipping out and lost sleep that night!! Then I came here (BYC) and found out it is fine to feed medicated as long as it has amprolium, which mine does and as long as I supplement with Niacin. My ducks seem very happy and healthy, except for a skin problem with one Pekin and I am looking to solve that one today.
I did purchase wild game starter yesterday, on the advice of a few more educated (than me) folks on here and will start them on it today. I just want to make sure they have Niacin. My Littles are 3 weeks old, and we don't seem to have had any problem with the Medicated Chick Starter. It is so odd to me how one feed store has one opinion and someone at another feed store tells another opinion about feed starter! That is exactly why I joined here
Let us know how things go!
Good Luck with your new babies...ours have brought us so much joy!
Blessings and L.O.V.E.
Pam