Cockerel with potential vision problems

[Qualien]

I have a young lavender ameraucana (sp?) Cockerel with lighter eyes than the rest of my flock. He seems to be okay, other than he is very sensitive to light changes, and doesn't seem to have peripheral vision. He follows movent in the front, but doesn't react to anything beside him, unless it touches him, to which he is immediately startled.

I was wondering if the color of his eyes is any indicator? The rest of my ameraucana flock has vibrant brown/orange eyes. To my knowledge he has always been this way. Could this be passed on genetically? Will it get worse? Right now, it isn't an issue, just wondering if anyone might know the causes of this.

 

[Eggcessive]

Unfortunately, his eye could be a possible sign of ocular mareks disease. Ocular mareks could be the only symptom of mareks that he has, or he could develop symptoms of the other types, including the skin form, the the nerve form or the form that causes tumors in organs. The ocular form can cause the pale color of the iris, and the small irregular shape of the pupil. Here is some reading about mareks disease:
https://www.backyardchickens.com/articles/the-great-big-giant-mareks-disease-faq.66077/

 

[Eggcessive]

Here are more links to read about Mareks:
https://extension.psu.edu/mareks-disease-in-chickens

https://extension.umd.edu/sites/ext...Preventing Mareks Disease in Small Flocks.pdf

 

[Qualien]

Thank you @Eggcessive I read the articles you posted, which were very informative. I'm not convinced this is Marek's disease, since he's been that way since pretty much hatch, and the rest of my flock appears to be very healthy. His pupils are smaller in the picture than they usually are, due to camera flash, but I will certainly be keeping a closer eye on him now. The only thing I saw that could be considered symptoms of Marek's would be the odd discoloration of his irises, and loss of peripheral sight... Though I can see how it would be hard to tell without any testing. I am wondering what else could cause that? Could it just be a simple birth defect? Marek's kinda seems like the Boogeyman of the chicken world. Grin.