Hi I have a very similar thing happening with my chickens this month, no respiratory symptoms, just swollen eyelid. We believe it is dry fowl pox, though mild (but the eyelid swelling not mild). It's transmitted by mosquitoes (I am in NH). It is VERY important to put terramycin ointment in their eyes as soon as possible to prevent further infection in the eye. It can be prescribed by a vet or available on Jedds for pigeons.
Unfortunately our rooster who had it first had a much worse infection happen in the eye, but the other chickens who got the terramycin immediately recovered quickly.
We had tons of tests done including all of the respiratory diseases (MG, IC, etc.) and they were all negative. Now we recognize the tiny black pox marks that we thought were peck marks, we are pretty certain it's fowl pox. There are also some black spots on they beaks.
Massachusetts will test your birds for mycoplasma for free btw.
Unfortunately our rooster who had it first had a much worse infection happen in the eye, but the other chickens who got the terramycin immediately recovered quickly.
We had tons of tests done including all of the respiratory diseases (MG, IC, etc.) and they were all negative. Now we recognize the tiny black pox marks that we thought were peck marks, we are pretty certain it's fowl pox. There are also some black spots on they beaks.
Massachusetts will test your birds for mycoplasma for free btw.