We have been using a non-GMO starter/grower feed for raising our Cornish Cross and they are doing well. It is milled in fairly small quantities by a Mennonite farmer. We DID start those birds on commercial chick crumbles and then moved on to the starter grower at around 3 weeks. I hadn't really noticed, but, having checked out the latest bag, there are a LOT of whole grains, large pieces of corn, and half split yellow and green peas. I DO have Chick grit out for the 50 layer chicks that turned up today, but notice that the large pieces are going through the 4 day old Indian Runner ducklings and ending up in their poo. Of course, the starter grit is tiny compared to the size of "pieces".. will it work in grinding down these large pieces of grain and pea? Should I forget using this for a week or two and go back to a commercial chick crumble?