When we got our chicks in August we had a bit of a dilemma. We had ordered both white rocks, which are broiler chickens, and red shavers, which are layers. Should we raise them in the same brooder box? The white rocks would definitely grow much faster than the reds. But, it is easier to only have one box to deal with, so we put them in together.
They all got along just fine. Although the white rocks quickly outgrew the reds, they are not at all aggressive, so there was no fighting or pecking their smaller companions. If anything the reds encouraged the whites to be more active. When the screened lid of the box was removed for adding feed or water the whites would sometimes attempt to fly out. This is not something we usually see them do.
So they grew and grew, and went outside to their movable pen. And there, in the sunlight and fresh air, they grew some more. Usually we would keep them confined to the pen until they are about the size of our silkie, a bantam chicken. This is to protect them, not only from potential predators like hawks or foxes, but also from being picked on by our other chickens or turkeys, who free range around the property. But when the whites had reached that size the reds were still quite a bit smaller, so we left them in another week.
They are enjoying being outside. The other birds did peck at them and chase them a little at first, but mostly they just go about their business and ignore them. Looking at them, it is hard to believe they are exactly the same age.
And they continue to grow and thrive. We move their pen daily to give them fresh grass to sleep on. White rocks do not roost, since they are so large they are not able to fly. The reds would roost, and they do sometimes hop on the feed trough handle, but usually they snuggle up to the whites right on the ground.
They still get along, even with the size difference. In a few weeks, when it is time for the whites to leave us and head to freezer camp they will be missed. But for now, they are all best buddies.