Hen with with odd pupil

[Poultry parent]

A while ago I noticed that one of my hens was limping so I went to check her out (the limo is now gone) while I was checking her over unnoticed that one of her eyes looked odd, almost as if the pupil had broken.


Its its been a month now, and she's acting fine, but her pupil still looked weird. I'm not super concerned about it because it doesn't appear to be hurting her. Though I still want to know what it is.





Does anyone know what caused it?

 

[Hillaire]

the one eye looks fine the other (her left) looks like she could have either gotten it poked or scratched.. is she blind in that eye? Doesn't look infected or anything so she should be fine..

 

[Eggcessive]

Do you know if she was vaccinated for Mareks disease? Mareks can cause an eye to change color, and change the pupil size and shape as well. Have you had any birds become paralyzed in one or both legs or wings, or have any tumors on the skin? Hopefully, this is just something else, but she may not be able to see out of that eye.

 

[Poultry parent]

All of my other hens are perfectly fine.
She isn't completely blind in that eye

 

[Eggcessive]

These are some examples below of how the eye form of Mareks disease can change the color and pupil shape in the eye of chickens.

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Left—normal chicken eye. Right—Eye of a chicken with Marek's disease

 

[Hillaire]

wow I had no idea that marek's caused the pupil to change... huh...

 

[Eggcessive]

wow I had no idea that marek's caused the pupil to change... huh...

Keep in mind that there are 4 types of Mareks symptoms--nerve, skin, organ tumors, and eye involvement. A chicken may have one or more of those. This hen may not have Mareks, but it is just a suggestion, Here is some reading about the disease:
https://extension.unh.edu/resources/files/Resource000791_Rep813.pdf
https://www.backyardchickens.com/a/the-great-big-giant-mareks-disease-faq