We are expecting a shipment of 30-odd chicks in about 2 weeks, all vaccinated for Marek's. This past week, however, we broke down and bought 7 chicks from TSC. The TSC manager confirmed that these chicks are NOT vaccinated for Marek's. We're concerned about putting the new arrivals in with these unvaccinated ones. There is no Marek's on our acreage, but will the vaccinated chicks shed the virus and infect the unvaccinated chicks? Our thoughts were to give the new arrivals a week to get over the shock of shipping and become acclimated to their new home before introducing the older chicks, since they're all going to share the same coop eventually. Should we wait a little longer to introduce them? Or not introduce them at all but keep them separate until adulthood (which would not be convenient at all)? Any advice would be appreciated.