After much long thought and internal debate i decided to vaccinate for Mareks disease. Mareks is a HIGHLY contagious airborne disease that's latterly everywhere! After talking to a doctor of poultry he helped me dispel some misinformation that i had once believed about the Mareks vaccine. I learned its ideal to vaccinate at hatch however it CAN be done at any age. The goal being to vaccinate BEFORE exposure to the disease. This is why they say to do it at hatch to lessen chance of exposure.another thing i learned was the vaccine is NOT the Mareks virus itself. It does NOT make your bird contagious as i once thought. There was just a really great radio internet show on this subject that the chicken whisperer did. I learned you CAN mix vaccinated birds with non vaccinated birds that the vaccinated birds WONT make UN vaccinated ill..so armed with new informed with new correct information i decided to do it! After injections my birds did NOT have any reaction at all! This vaccine is only given sub Q or under the skin.I'm really glad i did it and my girls are now protected. I just wanted to share.