I'm having repeating cases of what I believe is "nest box eye". Kits can't open one or both eyes due to some sticky gunk. It's very little stuff, but seems to seal the eye. I've been washing it off with a warm washcloth, and using some Vetricin eye ointment. They do get over it, and I've looked for an antibiotic ointment, but our feed stores no longer carry it. What causes this and what should I be using? Not every kit gets it, and they are 2-3 weeks old. Nest boxes have soft grass hay in them. Any help is welcome! Judith