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We have a Learning Center packed full of helpful articles written by our members about raising chicks and chickens, and more! Hopefully, you'll find a few article there that will help you.
Whilst this post is very old, so may the information given by members above. Higher levels of calcium are in layer feed. Too much calcium can cause kidney and other organ issues in chicks and roosters as they aren't able to use that much. But, some will say by the time a rooster would have kidney problems from too much calcium, they'd have died of old age. Still, many of us would rather not chance it so feed an all-flock to our chicks and chickens. That has less calcium, which is good for the chicks and roosters, but more protein, which is good for all. We give the hens oyster shell for added calcium in a dish or feeder separate from their feed. Those that need it eat it, those that don't won't.
