I have a hen that has matted eyes and keeps opening her mouth like she is going to throw up. (Visual only) I have about 20 other hens and am worried she may get them sick. What can i do for her and to make sure the others don't get sick to. I bought some agrimycin powder - oxytetracycline hci soluble powder. I do collect eggs and it says not to so I need to know what I should use. Or if all meds will say no eggs?