I have a lot of chick starter left and I'm not gonna waste it so I'm going to cut the protein level by adding oats. But that will also be cutting vitamins, and I don't want to skip out on those. Are there any multivitamins for ducks? Or can I just buy a bottle of multivitamins and crush them up? Which vitamins should I include in their diet, and which are toxic? Thanks, Katie.