Quote: I am so glad you did it. Realistically its probably the easiest transition for your cockerels.
In the best world, best case arrangements, they all need quarantined. My birds that needed rehomed are case by case. If I do not know the person, or know of them well through our thread, or close friends.. then they are locked away in my trailer. I go a full 45 day quarantine for birds that are unknown, example a neighbor drops by saying it was at the park, gas station or grocery running around. I rarely turn a bird away unless there is an obvious problem/illness, or the person is "pushing" me to take it in.. They all needed a home, and I let them come here. And the tossed out the window birds someone didn't want anymore. those get the 45 days. No kidding, I often find roosters and some hens I do not recognize, or know where they came from. Like stray cats here, "hey its a farm, they need our unwanted pet!"
If its someone I know, have spoken with a long time (thread members) or been to their home and seen their flock and husbandry, I will handle it differently. Again, case by case. Every bird I accept or purchase is examined when it gets here. I cage them, immediately. Watch the poop, is there worms, mites, lice? Vets will do a fecal very cheap. Free range to free range rehoming is different for me, its ever changing. I keep an egg flock, these are the misfits, the mix breeds and the birds that are not fitting a breeding program.
Do I always quarantine away from the main flock, NO. Do I cage and observe, absolutely. That bird has just left every thing it knows and had probably since it was a chick or hatched. It needs to learn, hey, here is where you sleep, eat and roost. This is your flock. That's the people that feed you every day. It also will be terribly stressed. It needs routine and the same people caring for it daily. It also needs its new flock, so its not feeling alone.
There are several risks. My egg flock eats a lot of natural things and some do pass with age. Hatchery birds seem to live 3 years at most, its pretty sad. I am seeing the worm "football" chases, or snakes, mice and even a wild bird on occasion. They are chickens, I let them be chickens and have a natural life as best I can.