When I have a mousie with an eye that looks like that I rinse it with eyewash. Plain salt water would do too. I rinse, then gently dry with a cotton ball and also gently pull the eye open a bit and rinse again. It works 75% of the time. It's usually just dust or some other particulate matter causing the irritation. Could be from the kind of bedding you use, or maybe you need better ventilation, as ammonia can irritate eyes as well.
I have no idea how many meeces you have and what kind of space you have them in. Mine are in a large walkin closet and have a large air cleaner in there, and I still have to wipe off all the surfaces each night, as they have visible build up of crud, probably mostly hair and dander.
I have no idea how many meeces you have and what kind of space you have them in. Mine are in a large walkin closet and have a large air cleaner in there, and I still have to wipe off all the surfaces each night, as they have visible build up of crud, probably mostly hair and dander.