As a newbie to chickens and BYC I have loved reading about the different feed suggestions. So I went to the feed store and got some whole Barley and Oat groats and some BOSS to stir up into my own chicken scratch. The cashier at the feed store, who has raised chickens for a long time, and has answered my many questions, told me not to feed whole grains to my 21 week chickens because it will clog up the crop. She especially says not to feed Milo or Millet, nor even sunflower seeds with shell. Now I'm worried, they do love the barley!!!