Hi, We've been regularly hatching chicks in incubators for awhile now and I've never seen this before. I can't seem to find anything in a google search either. Just noticed 2 of the chicks had swollen bloodied eyes this morning. Looked in a couple of hours later and I think it might be spreading. There is another one with just one eye like that.
There is no nasal discharge, and other than not moving very much because they can't see they otherwise appear not to have any other visible issues. These are some photos of one of the chicks. They are not picking on each other.
Thanks for any help!