Preventing pinkeye focuses on three main areas: 1) reducing eye irritation, 2) face fly control, and 3) nutrition. Another possible area is vaccination. A full pinkeye prevention program requires management of all three (or four) areas.
Eye irritation in beef cows and calves is a result of environmental factors. The principal eye irritant on beef operations is seed heads, grass stems, and weeds in pastures. Weedy or overgrown pastures force cattle to push their heads deep into the forage to select the more desirable growth. Seed heads and stems can cause physical abrasion to the eye resulting in an opportunity for bacterial infection.
If pastures are mowed or clipped they should be clipped low enough so cut stems are four inches or less in height. Simply removing the seed heads and leaving the stems may increase eye irritation. A combination of proper grazing management and clipping of pastures or hay making will decrease cattle eye injuries.
The key management strategy is good fly control. Fly tags are very effective for horn flies but less effective for face flies. In addition to fly tags, producers may want to use dust bags or face bullets. Bags and bullets can be located near salt feeders, but care should be taken not to accidentally contaminate the mineral source with the fly control product. Sprays are also an effective control method, but require more frequent application. Because face flies are not blood sucking flies, they are not easily killed by systemic or pour-on type fly control products.
Nutrition is essential to the health of all cattle. Proper nutrition results in good immune function which is important to disease prevention. Good forage management will ensure cows and calves receive adequate energy and protein to maintain animal health as well as produce heavy weaning weights.
Trace minerals are the nutrient most likely to be deficient in cows and calves grazing summer pastures. Specifically, selenium (Se) and copper (Cu) are very deficient in summer grazed pasture. Although these minerals will not prevent pinkeye, they are important minerals involved in immune function. Improved immune function will help cattle fight all infections including pinkeye.
Although several pinkeye vaccines are available, none of the vaccines provide complete protection against pinkeye. Producer satisfaction with vaccination programs is highly variable. Vaccination programs appear to be of most benefit in herds that have a high incidence of pinkeye. Producers should consult their veterinarian when considering a pinkeye vaccination program.
Jerry Little is Boyle County agriculture agent. For more information, contact the Boyle County Extension Office at (859) 236-4484.