I know that when you buy from a hatchery they talk about having vaccinated the embryos while still in the eggs and giving the day old chicks marek's vaccinations, etc. I will only have a small (4-6) backyard flock and I am hatching eggs for the first time to replace my flock that was eaten. Do I need to treat the eggs or newly hatched chicks with any vaccinations or medications? I haven't read anything about this so I hadn't thought of it until I thought of rehoming my excess chicks. I know alot of people only want vaccinated pullets for their flocks.