can i mix vaccinated chicks with non vaccinated 1 yr olds?

[wildorchid053]

i keep seeing about marecks and don't know if i should order chicks that are vaccinated.. will it affect my other group when i mix them?

 

[The Chickens' Maid]

Personally, I don't believe it would affect them, but I don't know for sure. When we ordered chicks, we opted out of the vaccination.

 

[Pampered Hen]

Mixing your vaccinated youngsters with non-vaccinated birds will have to affect on either group - if both groups are Mareks free...
Looks like you have suspicion that one of your hens is affected. I would not introduce new chicks to your home/coop if you have infected birds as the disease spreads rampantly.
According to an article, it takes about 10 days for the vaccination to take effect. By that time your new birds might have already contracted the disease...
Here is a bit more on the issue: http://www.shagbarkbantams.com/page9.htm