Hello, we started with our first chickens 2 and a half years ago. 46 day old chicks were delivered to us on March 2, 2010 - 10 from My Pet Chicken, 36 from McMurray, and ALL were vaccinated for Marek's. The first 'sign' was when a Speckled Sussex, Whirly Bird, had what appeared to be Wry neck, or crook neck. And the poor thing would always fall over backwards when she drank water. She was probably 4 weeks old at the time, but she got better. Then at 6 weeks, Laila our Silver Laced Wyandotte, became extremely lethargic and we nearly lost her. We treated the birds for coccidiosis, and she pulled through. We gave several birds away when they were a year old, but everyone was healthy. We had also adopted a Cochin rooster that was a little younger than the girls. He was a lovely boy and he appeared healthy, but dropped dead rather suddenly at 1 year old, that was June 30, 2011. 2 weeks later a Jersey Giant died from a mysterious cause. A few months later, Whirly Bird's eye started to look a little funny. Like she had a cataract in it, and the pupil started to look elongated and narrow, but she seemed healthy, so I assumed it was an injury. So now lets fast forward to summer 2012...Laila my sweet SLW was found dead in the run last month. She was out and running around the day before, acting like her usual bossy and noisy self. Whirly bird's other eye is clouding over now, although not as bad as the first eye...yet. I noticed 2 nights ago that her 'sister' Frosty, another Speckled Sussex, has a cloudy eye as well. Frosty had been a beautiful bird, but her feathers are a mess now, with many missing all over her body; Whirly isn't much better. We also had a Rhode Island Red, Trudy, who had a very large, sour crop. She died as well. Perhaps the cause of that was Marek's, since it can affect the Vagus nerve... Again, all birds are vaccinated for Marek's, but I know that isn't a 100% safeguard. The 10 from My Pet Chicken look good, the the others I worry about. I will get pictures of the birds tomorrow. I have spent the afternoon reading about Marek's, and I feel quite certain that my Sussex girls have Ocular Marek's. And perhaps Laila didn't have coccidiosis, but Marek's when she was 6 weeks old. I am thinking that my flock has Marek's. I realize that there is no treatment for this, but I would like to know definitively. Can a live bird be tested? If this is Marek's, what can I expect in the future? Will more die off unexpectedly? I assume that I cannot introduce birds that have not been vaccinated, right? I love my girls, all of them are named, they are VERY tame, so culling is out of the question. Ugh...this is rotten. Any help/replies/advice would be greatly appreciated. Thank you!!