Over the last two weeks my sheep seem to have developed a contagious eye problem and I'm not sure what it is. Symptoms are slightly cloudy eyes that they are reluctant to fully open, with tear staining on their cheeks. I'd say that about 40 of the 130 adult sheep are now affected in one eye, with two ewes showing symptoms of blindness with both eyes affected. They are never fed in troughs and haven't seen any hay or silage since May, and hadn't been gathered for over a month when I noticed the first sign of it so it must be highly contagious. I had the cast ewes in yesterday and sprayed Alamycin spray on the infected looking eyes, but if it is as contagious as it seems am I just wasting my time and it will run its course to no long term damage? Or do I spray all troubled eyes?