I have a rescue Aussie mix?? He is six to eight months and has one blue eye and one brown eye. The brown eye is off and on irritated (bloodshot) and winks more than the blue eye, sometimes when he is tired it doesn't open as much as the blue eye. It doesn't seem to cause him distress. He has been on antibiotic and prescription drops which have not changed the issue at all. Any suggestions would be helpful.