Late summer is the time of year when it is (usually) the easiest to own cows. Calving is over, the calves have had their spring shots and are out frolicking in the pasture, and the cows are just eating grass and chillin’. But like ants at a picnic, something has to creep in and ruin an otherwise lovely time. Enter the disease called pinkeye.
Pinkeye in cattle is a disease of the eye caused by the bacteria Moraxella bovis. We are also learning that another bacteria, Moraxella bovoculi, can also cause pinkeye. The disease starts with any sort of scratch on the cornea of the eye, from something like the switch of a tail taken to the face or a blade of grass scratching the eye as the animal grazes. In this tiny wound, the bacteria sets up shop. Pinkeye can quickly progress from a small corneal ulcer to a cloudy, inflamed mess. If left untreated, the eye may not recover, resulting in blindness and/or corneal rupture.
Obviously as ranchers we do everything we can to prevent the disease from occurring. Doing so is a multifactorial process. At our ranch, we use vaccination for both types of bacteria to start with. We control flies, that can spread the disease, by use of insecticide permeated fly tags the cattle wear and topical fly treatments. We also remove hay contaminated with manure the cows trampled on during the winter, which flies like to use for breeding. In addition, we also try to manage our grazing so the cattle don’t graze pastures with tall, mature grass that can scratch eyes.
Unfortunately, prevention is not always 100%. That’s why checking the cattle frequently is so important, so we can catch the disease early for timely treatment. Treatment includes using an antibiotic to combat the infection, and then covering the eye to block UV radiation that slows healing. One approach that works pretty darn well is to glue a patch made from old blue jeans over the eye. It also makes the calf look like a pirate, which is pretty rad.
With good prevention and timely treatment (if prevention isn’t 100%) the cattle can focus on growing and frolicking. And ranchers can focus on the lazy, hazy days of summer. Haha, who am I kidding, it’s haying season!