Purina Organic Starter/Grower Crumbles

[rtrodr90]

We fed our two ducklings Purina Organic Starter/Grower crumbles and within a couple hours the first duckling died. The next day the second one passed. The ducklings were fine and the next second were on their backs feet up. I have never seen this before.
I went to my local feed store and they made me aware that this is what killed the ducklings. Before I make a huge stink at the tractor supply store, is this correct information?

 

[Barnes599]

It's not the chick fed it's self that killed them, it's what it's lacking, next time supplement with brewers yeast tablets, or niacin.