My SILKIES are now 3 weeks old. I received them from MypetChicken . They advised me that they do not vaccinate Silkies for Mareks or any other disease. I was advised on the reasoning behind their theory. My question is: should I be lucky enough to find an aviary vet as I was told my family vet does not vaccinate chickens,then at what point in time should the vaccinations occur?