I use this in my feed A Braggs Nutritional yeast.@Sarkchick - PolyViSol withOUT iron is what is considered safe.
All, I am wondering if their Walmart has this http://www.walmart.com/ip/Nutritional-Yeast-Seasoning-Bragg-4.5-oz-Flake/30291183 if it should work,
I went back and reread my post I said with out iron please be sure if you give the duckling poly vi sol it doesn't have iron in it.