How soon is it recommended to provide an area in the brooder for dust bathing? Is it even necessary this early on?
Its not necessary. They'll bathe in the shavings if they don't have dirt. That being said, I always keep a pan of dirt in my brooder, even when they're tiny day olds. My brooder is outside, and I figure they'll have access to bugs that seek out the heat lamp (when it isn't freezing and snowing anyway), so they'll need the grit they get from the dirt. If you're brooding in your house, I would NOT give them dirt to dust in. They'll make a mess, you'll have dust all over everything (you'll have dust all over everything anyway, but a dirt bath will make it worse). If all you're providing them to eat is crumble, they don't need grit. And they'll find a way to take a dust bath whether you give them dirt or not
Yes, they will bathe in the shavings. I give my chicks a clump of sod on a pie tin even if they're in the livingroom. The dust from that is IMO no where as bad as the dander that they shed on a daily basis.