Help! One chick died from Marek's, now another one sick

[BAMillis]

I bought 6 chicks and they're about 12 weeks old. One (silver laced Wyandotte) was not vaccinated against Marek's (I just found out), and she got it and died (had a necropsy done). Now another chick (Ameraucana) is showing the same symptoms: not able to pick up her head, won't/can't eat or drink, just lies there! Poop is a little runny, but not bad. They eat Purina start & grow, I feed them some yogurt about every other day, and lettuce/greens each evening. I give fresh water every day, and clean/clorox the waterer every few days. They are in a Catawba Coop in a natural area with a thick groundcover of leaves (I rake out one end so they can get to the dirt for their bath). I move it once a week, and clean out the pine shavings from the roost once a week. If she was vaccinated, then it can't be Marek's, right?? Any ideas??

 

[Judy]

As I understand it, there are several types of Marek's, and the vaccination does not protect against all types. When you put vaccinated and unvaccinated chicks together, you are exposing the unvaccinated ones to the disease, which is shed by the vaccinated ones.

But I'm certainly no expert. Sounds like you need to do some research.