One of my hens (5 months) has marks on her right iris. I heard that problems involving misshapen pupils could be Marek's, but their pupil seems to be a perfectly round shape on both sides of their head, they just have some greyish dots. They kept squirming when I was trying to take a photo of them so this is the only one I could find.
I'm uncertain about how long they've had this.
They weigh the same as their twin sister that does not have any marks or abnormalities in their eyes. She's very active and her poos seem healthy.
Thank you for the help