Your problem is that you are getting chicks from a farm, who may or may not have been exposed to Marek's disease there. Your hatchery Marek's vaccinated chicks need two weeks BEFORE any exposure to Marek's disease virus to develop protection. So those Marek's vaccinated chicks need to be totally isolated from any other chickens, or their possibly contaminated environment. It's spread by dust, feathers, whatever involoved with diseased birds or their environment.
And feeding amprolium medicated feed, even one meal, will negate whatever the coccidiosis vaccine was meant to do. It won't harm the chicks, but the coccidiosis vaccine won't do them any good.
So, as far as Marek's vaccine is concerned, it's not about those other chicks not being vaccinated, it's about what they might or might not bring with them from that farm.
Two entirely different products, and concerns.
Mary
And feeding amprolium medicated feed, even one meal, will negate whatever the coccidiosis vaccine was meant to do. It won't harm the chicks, but the coccidiosis vaccine won't do them any good.
So, as far as Marek's vaccine is concerned, it's not about those other chicks not being vaccinated, it's about what they might or might not bring with them from that farm.
Two entirely different products, and concerns.
Mary
