Marek's vaccine dosage for older birds?

[jewel1]

Hi everyone..

After much debate, I've decided to vaccinate my four 20-week old pullets for Marek's since they were not vaccinated at birth. I understand that it may not help them much, but I'm going to try anyway.

I believe the dose for day-olds is 0.2cc subQ at the back of the neck. I cannot find any dosage info for older birds. Is it still 0.2 cc?

thanks

Julie