Battling Pink Eye in cattle

Gary Sliworsky
Ag. Rep.

Pink eye is estimated to affect 20% of calves and 10% of feeder cattle. It is an irritating and painful disease of the conjunctiva (soft tissues around the eye) and cornea (clear part of the eye). Economically it can have serious impact on weight gains, treatment costs, labor, and it can decrease the value of an animal by permanently disfiguring or blinding the eye.
The bacterium most commonly involved is often found on the eyes and nostrils of healthy animals. Disease occurs when conditions encourage these bugs to multiply on the eye in large numbers. Irritants that start the bacteria growing include UV light, fly bites, or physical trauma from things like long grass, dust, and chaff. A lack of pigment around the eyes of cattle and other infectious diseases such as IBR also play a role. The bovis bacteria and thus pink eye is spread by direct contact between cattle, their rubbing on common areas, or by flies.
Early symptoms include excessive tearing, blinking, and eyes that appear pink around the edges. In severe cases the cornea looks white with visible ulcers.
There are many treatments. Generally, long-acting oxytetracycline given systemically (in the muscle or under the skin) is effective but a second injection may be required 72 hours later. For topical treatment there are many mastitis medications that are quite effective (this is off-label use and you should discuss it with your veterinarian), but, if used as the sole treatment they should be given daily for 3-5 days. A combination of systemic and topical treatments gives best results.
For prevention, control flies with insecticide ear tags (ideally in both ears), oilers, dust bags or face rubbers. You could also mow over-grown pastures to reduce dust, pollen, and long grass, segregate infected animals, and provide shade from UV rays in pastures. There is a vaccine available for pink eye, however it seems to decrease the severity of disease more than prevent the occurrence.