There are several broody hens in our coop, and we may be getting a few more chicks. I figured that we would buy some chicks from either Meyers or Cackle, and have them vaccinated. How long do I need to quarantine them? And is it for their sake, or for our former flock's sake? I understand that people allow their chicks to interact with their flock all the time, if their hens are brooding the chicks. But have no idea if it safe to do so, if I have the chicks vaccinated so recently? Our flock have come from both Meyers and Cackle, and all were vaccinated for Marek's. Could they be carriers of Marek's because the have the vaccination, and then give it to the chicks who have not received the immunity quite yet? or could the chicks give Marek's to the hens and roosters? I have also generally heard not to introduce the chicks to adults because they lack a certain immunity, but people have been doing it for generations upon generations. Of course, with some casualties, but maybe we are over complicating things just a little? And, if I waited to introduce them to a broody hen once they are 1-14 days old, would an extremely broody hen still accept them?