My pullet's leg joint is red and swollen, what's wrong?

[lbc1]

She's been a little lethargic for a few days but she kept perking back up so I didn't think it was serious. I'd been giving her electrolytes in her water. Tonight I decided to bring her in since she was still looking a little down and I noticed right at her lower leg joint where the feathers end, she has an ugly scab, swollen up and a few red swollen spots on the same leg. The other leg is fine. Her feet are a little cold to the touch and she's breathing heavy now, but still eats, drinks and walks around. I don't think it's bumble foot ... Could this be marek's related? I've lost some chickens to it earlier this year. Just a cut maybe? I went ahead and started antibiotics in her water once I saw the scab.

 

[lbc1]

I put some neosporin (not the pain relief kind) on the spots... It looks like a cut at the leg joint, where the scab is. Could the other red, raised spots be signs of infection?

 

[Eggcessive]

Has she had any respiratory symptoms?

 

[lbc1]

She's been breathing a little heavy, sometimes she opens her mouth slightly to breathe, but her eyes and nose are clear and clean. No sneezing or discharge.

 

[Eggcessive]

You might look up mycoplasma synoviae to see if it sounds like that--just Google it. I can't post any links right now. There are some Mareks people on here who might have an opinion.