A heavy population of face flies has appeared in southern portions of the U.S., triggering concerns about costly pinkeye outbreaks. With peak fly season on the horizon for all parts of the country, now is a good time for producers to get ahead of pinkeye to prevent production losses and labor-intensive treatment.
Pinkeye is most common in late spring, summer and early fall, with flies playing a major role in transmitting the disease from animal to animal. And while pinkeye may be a seasonal disease, it ranks high on the list of most expensive cattle health issues.
For preweaned calves pinkeye is the second most costly disease, behind only scours. One study showed a 17-lb. weight loss when one eye was affected and up to a 65-lb. loss when both eyes were involved. All told, pinkeye affects more than 10 million calves annually, resulting in economic losses topping $150 million per year. 1
According to Dr. Doug Sholz, director of professional services, Novartis Animal Health, most producers who’ve experienced a pinkeye outbreak are highly motivated to prevent it from ever happening again.
“The treatment and management of pinkeye is extremely labor intensive,” said Scholz. “Typically, when a producer goes through a severe outbreak, they’ll make pinkeye vaccination a part of their annual herd health program. Once they’ve seen the impact firsthand and realize how significant it is, the cost of prevention pales in comparison to losses that come from an outbreak.”
Scholz said that treatment for pinkeye can include injecting medication into the tissues around the eye, or even suturing the eyelids closed so that infected tissue can heal. “Either way, the course of treatment requires lots of animal handling and lots of labor. And on top of that you have decreased productivity from a rate-of-gain standpoint,” he noted.
What Causes Pinkeye
Pinkeye is a highly contagious, infectious bacterial disease of the eye caused by Moraxella bovis. Contributing factors include anything that can irritate a calf’s eyes, such as ultraviolet light from prolonged sun exposure or airborne particles like dust and pollen.
Feeding practices can play a role in pinkeye. When animals eat out the middle of round bales, leaving a hay shelf over their heads, the likelihood of irritants getting in the eyes increases substantially. The same situation occurs when hay is fed in overhead feeders.
Viral diseases like IBR and BVD that compromise the calf’s immune system can make them more vulnerable to the Moraxella bovis bacteria. Flies not only serve as irritants to the eye, but they also transmit the bacteria from infected to noninfected animals.