Yes, and no. Conventional wisdom says that if they just eat chicken feed, they do not eat grit. However, there are plenty of folks who counter that statement by saying: God designed chickens with a gizzard which is designed to hold little stones or grit to help grind their food. Those gizzards NEED grit to develop properly. And your chickens will eventually be eating something other than chicken feed, I presume. This is what I like to do: I start my chicks on fermented feed in the first week. (be sure to put it in something that they can't fall into.) Initially, I just plop it on a scrap of wood or cardboard. Then, into a shallow container. After they are filling their crops nicely, I introduce them to a plug of sod from my yard (be sure you haven't used any herbicides/insecticides) I use a piece about the size of a pie plate, and place it upside down, right in the litter. They go nuts over it. They get: a bit of grit, minerals from the soil which they WILL eat, their first greens, a healthy dose of micro-organisms to improve their gut flora, a few tiny insects and maybe seeds, and their first dust bath.