I have a duck that seems fine but her right eye is cloudy and she can't seem to see with it anymore. The left eye is clear and bright but the right is cloudy and I can't see a pupil. Are there some drops I can get? It doesn't really look like an infection so I didn't necessarily want to use Tetramycin. Though I've had good luck with it in the past. She is getting old, about 6 years if I remember right.