Pinkeye is the most common eye disease of cattle and Dr. Peter Constable from the University of Illinois indicates the disease costs cattle owners 150 million dollars per year in reduced rate of gain.  Pinkeye is a bacterial disease that is transmitted from cow to cow directly or mechanically by flies.  It commonly occurs in the summer due to increased flies and usually occurs in calves less than 1 year old.  Like cancer eye, it is more common in cattle with white faces like Herefords and Simmentals.  It has been shown that wind, dust, grazing in tall grass, and anything else that can irritate the eye can predispose calves to pinkeye.  Symptoms are conjunctivitis or inflammation in the tissues around the eye and ulceration of the outer membrane of the eyeball called the cornea.  These eyes are red, inflamed, tear excessively, and are painful as the calves squint their eyes. 

Up to sixty percent of these eyes will heal without treatment.  However, I do believe treatment decreases the damage that may occur to the eye.  The most economical treatment is LA-200, a form of oxytetracycline that is effective and is injected into the muscle twice at 3-day intervals.  Antibiotics Nuflor and Naxcel have also been shown to be effective given in the muscle.  However, I believe the best treatment is for your vet to inject gentamycin and cortisone directly on the surface of the eyeball in the membranes surrounding the cornea as this is more effective in decreasing damage.  For many years, antibiotics such as penicillin were injected up into the eyelid but this treatment has been shown to be ineffective.  Prevention of pinkeye involves controlling flies and mowing pastures.  A vaccine is available and has been shown to be somewhat effective at reducing incidence of the disease in some herds.