My original, mixed flock came from Welps Hatchery last year. They were all vaccinated for Marek's. My question is now that I'm ordering from individual breeders (who don't vaccinate for Mareks) is this something I should do myself? and, if so, can I get this at a feed store or do I have to go thru the vets office? Does it matter how old the chicks are? I don't show although maybe in the next couple of years and so I don't come into contact with a lot of different birds, but do occasionally visit friends that have birds. Does anyone have a link to a thread on a discussion about this I can read? I'm looking but am having trouble locating. Thank you!!