~Suddenly half blind hen~

[TheOddOneOut]

Definitely Ocular Marek’s.

 

[RoosterWhisperer]

You could have brought home the Mareks' virus on your shoes from anywhere. It doesn't have to be from somewhere that there's active Marek's, either because Marek's virus is so durable in the environment, it can last months on surfaces and in soil, sometimes years under some conditions, and can be transported on soles of shoes, car tires, farm implements, etc.

I've never seen an eye injury present identical to ocular Marek's. It's unlikely to be an injury. The only way to verify if you have Marek's in your flock is to have the next chicken that dies tested.

Once you absorb this possibility your flock has Marek's, you'll see little has changed. Even this hen with ocular tumors may live a long, otherwise normal life. You will just be dealing with a symptomatic chicken from time to time, each case possibly slightly different, some serious, some with symptoms, like my old hen, that can be managed so they can lead a comfortable life.

Definitely Ocular Marek’s.

Okay, thanks! She's very healthy otherwise and I don't have any lame birds so I'm not too worried about it now!

She'll probably lead a long life so that's good!