I have an outdoor brooder inside our run. I have 3 and 4 week olds in the brooder right now, and I started doing this 2 months ago with the first hatch. I read that it is a simple way to expose them gradually to the area they will be integrated. I put the dirt into a corner and they end up incorporating it into the wood shavings. But there is some dust bathing going on before that!So adding a small amount of dirt, daily, to an indoor brooder is a very important, whether or not one’s chicks get medicated feed.
I feed medicated feed to those chicks, continuing when they are moved to the "ground floor." When they are introduced into the flock everyone gets regular unmedicated starter/grower.