I have a 6 week old chick that has been struggling to grow. I will include a picture of her next to her sister. They are same breed, same age. For weeks now she has been scratching at her eye, and now today I see that it is strange looking. It looks huge compared to the other eye. She was Mareks vaccinated at one day old. I had a verified case of Mareks on my property two years ago, but it was NOT the ocular strain. Can the other strain turn into the ocular strain? It seems unlikely to me. I also have seen in pictures that ocular Mareks causes misshapen pupils. Her pupil looks big and round to me, not abnormal. Can anyone tell me what might be going on with her eye please??