Pink Eye Protocols
Producers Have Numerous Options When It Comes to Pink Eye Prevention and Treatment
For many producers across the Cornhusker state, it has been a heck of a spring. After parts of the country experienced a polar vortex in February and a late-spring blizzard in March, many beef producers were elated to get their cattle out to grass. With some sunshine and a renewed perspective, producers may be turning their attention to disease control, including being on the lookout for pink eye.
“It’s difficult because it’s different from year to year,” says Cori Stava, DVM, Cross Creek Animal Health Center, Staplehurst.
Prevention is key, and there are numerous ways producers can avoid the prevalence of pink eye, including pour-ons, sprays and rubs; fly tags; and even immediate-release and programmed-release implants. Many producers, however, have found vaccination and feeding an insect growth regulator (IGR) mineral to be extremely effective prevention methods.
In Stava’s experience, the best preventative for pink eye is vaccination. For a little more than $1 per dose, beef producers can vaccinate with a commercial pink eye vaccine that specifically targets the Moraxella bovis bacteria, which has historically been identified as the primary agent of infectious bovine keratoconjunctivitis (IBK) – aka, pink eye.
However, in recent years, practitioners like Stava have had increased difficulty in preventing and treating pink eye because the multiple-strain variations of the bacteria are constantly mutating.
“In my experience, the most common strain lately has been Moraxella bovoculi,” Stava points out. “That’s the reason I prefer the autogenous vaccine,” she says, in comparison to the commercial vaccine.
An autogenous vaccine is a killed bacterin created from the disease-causing organisms. Stava produced her own autogenous pink eye vaccine by swabbing the eyes of multiple cattle with pink eye symptoms in her service area, creating a unique population. Those samples were then sent to a lab where the bacteria were cultured, or grown, and then utilized to develop a vaccine to help build immunity within the specific population.
Stava’s vaccine targets Moraxella bovis, Moraxella bovoculi and Mycoplasma bovoculi. Mycoplasma is a bacteria without a cell wall. “Many antibiotics, such as penicillin, cephalosporin and any antibiotics derived from them are only effective against bacteria with a cell wall,” she explains. “There are some approved injectable antibiotics to treat Mycoplasma; however, it’s difficult to get high enough tissue concentrations to eliminate Mycoplasma, which is why treatment results are variable.”
At a cost closer to $2 per dose, label instructions for the autogenous vaccine call for 2 ml to be administered subcutaneously, followed by a booster dose of the same amount two to four weeks later for calves. For adult cattle that have already received that vaccination protocol and have built up some immunity compared to younger cattle, Stava recommends a single-dose vaccination annually.
Another way to practice pink eye prevention is through a complete mineral program that includes an insect growth regulator (IGR). Travis Schauda, district sales manager for Vitalix Inc., explains that fly control is one of the most effective ways to prevent pink eye.
“Anytime you reduce the fly population, you are going to reduce pink eye,” he states. “With fewer flies in your herd, the risk from pink eye goes significantly down.”
IGR is a supplemental ingredient that prevents adult horn fly emergence from the manure of treated cattle. Existing adult horn flies aren’t affected by IGR, so Schauda recommends starting feeding before horn flies appear.
“Preferably, producers should start feeding IGR the week of the last Nebraska frost,” Schauda advises, though he points out that that time of year can be hard to predict. As an alternative rule of thumb, he suggests starting to feed IGR at least a week before cattle go to summer grass and stay on it until the second frost in the fall when the weather is consistently cold enough to mark the end of the horn fly season.
Compared to a base mineral and depending on the inclusion rate of IGR, producers can expect to pay anywhere from $100 to $165 per ton more for mineral tubs that include IGR. Schauda always recommends producers follow label directions when feeding mineral, though most allow free choice to cattle.
Even with protocols in place, complete prevention of pink eye isn’t guaranteed. Early symptoms of pink eye include watery eyes, or an animal constantly closing its eyes or avoiding bright sunlight. As the disease progresses, the eye can become cloudy or white as the infection, an ulcer, spreads across the cornea. In the most extreme cases, the ulcer can penetrate completely through the cornea, resulting in the iris protruding through the ulcer.
In the event an animal needs treatment, time is of the essence as early treatment can likely save the eye. Stava recommends treatment with a long-acting oxytetracycline, like LA 200. In severe cases, Stava will treat with tulathromycin (Draxxin) and, as a last resort, may suture the eye shut.
If a producer is having issues with pink eye, a check of the environment to see what may be causing the distress is good idea – things like flies, plant material and excessive dust or sunlight could be possible irritants.
“The more horn flies a cow has, the more stress she has; the more stress she has, the higher her heart rate is,” Schauda reminds producers. “When her heart rate goes up, that female may require more feed and water, her milk production may go down and her estrus cycle may not be as strong.”
Highly contagious, pink eye is easily spread when one animal comes into contact with the infected secretions of another animal. Flies can carry the Moraxella bovis bacteria for up to three days, spreading it from animal to animal. In individuals or whole herds, infection can result in decreased weight gain, low milk production and high treatment costs.
Working with a veterinarian and/or nutritionist in your area to establish a prevention plan and contingency plan for treatment is a producer’s best bet to combat pink eye this summer and every year.
By Micky Burch, Nebraska Cattleman Assistant Editor