I've been doing a lot of reading about what to feed ducklings and chicks. I have 8 chicks and 3 ducklings together in the same pen and they are doing great, but I have been reading that you are supposed to give growing ducks brewers yeast. If I mix brewers yeast into the feed that I feed to both chicks and ducklings, will it harm the chicks?? I haven't bought any yet...heck, I can't even FIND it. lol Just want to make sure before I do that it won't harm my chicks. Thanks!