Well if they can free range together that would be a good way to start introducing them together. You will also need to have a plenty big enough pen so the chicks can escape the older pullets. Also if your going to let them live together full time you’ll need to find someway to feed each other spereate because the chicks should be in growers feed and hens should be on layers. Hopefully I helped but im sure other people who know more about this will come along and give a good answer.
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