I'm sorry, I've forgotten what breeds you keep and where you live. Do you have particularly fragile birds and a harsh climate?
I'm fortunate that my chicks have mainly be fast-maturing breeds who feathered out early (brooding outdoors helps with that). There's only one batch that wasn't in the...
Since I brood outdoors I start them on medicated feed until they've been in the main coop for a week or so then switch them to all flock like the rest of the chickens.