We've had a closed flock bar bought in tups for over ten years. This year as we were low on stock we bought in a batch of mules with lambs at foot, now about four or five weeks later, pinkeye is going through our own ewes like wildfire, the mules are unaffected. We've been treating them with a jag of terramycin and opticlox eye tube which has been clearing them up. This morning I see some ewes which have been treated and appeared to be better becoming reinfected. It's now a real problem, have any of you had a similar experience and is there other better treatment options than mentioned above?