Rooster limping after cold spell

[MyCircusMyMonkeys]

Hello friends! I've contacted my vet (who I think tries to be emergency-only on weekends) but thought the fine people here have seen a lot of limping chickens and might be able to shed some light.

Our rooster, Prince, is 10 months old and has started limping in a quite pronounced way:

He hasn't been exposed to any new chickens, but he was interacting with two of his brothers more during the cold and could absolutely have landed funny getting out of their way. This being said, I don't feel any swelling, can't find a cut or wart/mite/etc, and he doesn't seem to be in pain. His appetite is great and his droppings look normal. In addition, I've been worried about a slight mismatch in eye color for months now, though it's hard to capture both eyes in the same lighting:

I'm sure you all know what I'm worried about here. Does this look like Marek's to you? I read somewhere about green droppings, which I haven't seen, but I know the disease can be a grab bag of symptoms.

We're keeping him separated, though full biosecurity is going to be hard to achieve, and are adding nutritional yeast and kickin' chicken supplements to his food in case it's a vitamin deficiency.

The reason I think it could be Marek's is because we brought a chicken home six or so months ago and—idiots!—didn't quarantine immediately. She was in rough shape (worse than we realized) and passed soon after we got her. The other chickens we brought her home with had some respiratory issues but recovered just fine after a course of antibiotics. So there was a possible infectious event ages ago. We had a young hen die last November and did a necropsy, but her diagnosis was reproductive issues followed by bacterial infection. There was no mention of Marek's in the necropsy results, but I don't know if that means anything.

Please lend your expertise if you can! Thank you for your time.

 

[Wyorp Rock]

Why are you keeping him separated, just to keep him from moving about so much on his injured leg?
If you are concerned that he may have Marek's, all the birds he's been with have been exposed, so isolation, quarantine would be futile at this point.

It looks like he's suffered injury to the leg, but it's hard to know. I'd treat it as such and see if he improves over time.

As for the eyes, yes they are different, so it's possible this is Ocular Marek's, but again, testing would be the way to get concrete answers, so if you do lose him, having a necropsy would be the best thing to do.

Here's some photos of Ocular Marek's.
https://www.backyardchickens.com/threads/ocular-mareks-with-pics.1587096/post-26970258

 

[MyCircusMyMonkeys]

Thank you so much for the response and the linked post! I assumed a bird suffering from a Marek's flare-up would be shedding more viral particles and thereby be more likely to cause a resurgence in the others, even if they're already carriers. (Like--there's a threshold their system can handle, or something.) That could well be complete BS, but since it's helpful for him to move less I didn't examine the notion very closely! I've had a really hard time understanding how the disease works as you can probably tell When we got the necropsy results back for our hen and there WASN'T Marek's I thought that meant my flock was in the clear, but I guess it might not show up unless it's active? I feel like an idiot. I studied microbiology as an undergrad, believe it or not, but we only scratched the surface re: how viruses work and I've forgotten a ton besides.

If a chicken's eyes change color, is there ever anything else it could be? His pupils react normally to light and his vision seems good based on how well he can aim. I'll admit I was kind of hoping someone would bust in here saying "oh that's definitely an [insert medical term here] hip" or some such thing Hope springs eternal! If we lose him I'll definitely get a necropsy and report back.

Today when I was feeling his legs I did wonder if I could feel more of a difference in where the hip (or I guess knee??) is. It's possible there was swelling I didn't recognize as such, or I'm imagining things. What I don't get if it's an injury is why he seems so chipper and willing to walk on it. That's what really freaked me out and made me think it was a nerve thing; if it was hurt, surely he'd be acting hurt? As you can tell, I'm new to the rodeo... Anyway, thank you for letting me go on and on! If you've read this far Will do as you say re: treating as an injury. He quite enjoyed his first epsom bath a day or two ago.