Well, it really depends on what your shooting for. If your wanting to process them in about 16 weeks you want to go with the higher protein feed (22%). If your not really worried about it, you can just let them all hang together and when the roosters get to the size your looking at..... usually 22 weeks for Dark Cornish you can just feed a standard chick grower.
Dark Cornish do take a few extra weeks to fill out, similar to a Buff Orpington. But yes, DC or not anywhere near the size of the Cornish x's and will fare just fine with your other dual purpose breeds in the brooder.
Dark Cornish do take a few extra weeks to fill out, similar to a Buff Orpington. But yes, DC or not anywhere near the size of the Cornish x's and will fare just fine with your other dual purpose breeds in the brooder.