The price tag of pinkeye in the U.S., including decreases in weight gain, milk production and treatment, is estimated to be $150 million.

More than 10 million calves are affected annually, and the resulting weight loss can be up to 65 pounds per head.

Pinkeye occurs in all age groups but is most common in calves. Pinkeye is the most common condition affecting breeding-age heifers. Bull calves have a higher susceptibility than heifer calves.

Most pinkeye cases appear during the late spring, summer and early fall. Ultraviolet light, physical irritation and poor fly control sets the stage for infection of the eye with Moraxella bovis, the most common culprit in pinkeye.

Although pinkeye is generally associated with the seasons with the most sunlight exposure, winter pinkeye strikes cattle, too.

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Cattle in close confinement are most susceptible to winter pinkeye. UV light reflected off snow or irritations from winter feeding are common causes of winter pinkeye.

Manage to prevent pinkeye

Management matters when it comes to avoiding many health issues, and pinkeye is no exception. Pinkeye treatment is labor-intensive and expensive, so prevention is the best medicine.

  • A preventive vaccine can be given at the start of pinkeye season and is the greatest insurance against pinkeye. The best time to vaccinate for pinkeye is in spring or early summer, before the start of fly season.
  • Face flies, house flies and stable flies feed on eye secretions of infected cattle and transmit pinkeye from animal to animal. Face flies can remain infected with the M. bovis bacteria for up to three days after feeding on infected material.

    Insecticide fly tags, sprays, back rubbers and dust bags can provide chemical control of flies. Keep in mind that flies build resistance to pesticides, so better results may be seen by alternating the pesticide class annually.

  • Feed additives, such as insect growth regulators, can target maggots laid in manure and are especially useful if an operation commingles new cattle. Dung beetles also decrease egg survival and should be encouraged.
  • Manure, weeds and brush should also be managed to minimize flies. Certain grasses – hybrid sudangrass and forage sorghums, weeds and brush – create pollen and chaff that serve as airborne mechanical irritants for cattle.

    Mowing, spraying and managing grazing can help minimize flies and reduce plant irritation.

  • Hay feeding methods can stimulate eye irritation. When cattle eat the middle of a round bale and leave a hay shelf above their heads, the hay can aggravate the eye.

    Overhead hay feeders create the same irritation. Cattlemen may see benefits from spreading the hay out or lowering haybunks.

    Some types of hay, such as wheat hay, hay with cheat grass or mature seed heads, also compound the irritation.

  • A balanced nutrition program helps cattle resist pinkeye. Cattle deficient in key nutrients such as protein, energy, Vitamin A, copper and selenium are more susceptible to bacterial diseases.

    The nutritional impact of weather events, exacerbated by prolonged drought in some areas, has lowered resistance to pinkeye.

  • Breeding for eye pigmentation, which is highly heritable, and planting shade trees to block UV light can be advantageous for cattlemen.
  • Another cause of pinkeye is the prevalence of other diseases. Infectious bovine rhinotracheitis (IBR) has been linked to cases of pinkeye as well as its severity.

    Bovine viral diarrhea (BVD) also compromises the immune system and makes an animal more susceptible to diseases like pinkeye.

    Preventing cases of any disease will reduce the overall concentration of bacteria on a farm that can cause pinkeye.

Keep an eye on warning signs

Despite best management practices, cattlemen should be prepared to act quickly if pinkeye strikes. Cattle will usually recover with minimal or no permanent eye damage if affected animals are detected early and treated aggressively.

Cattle with pinkeye will show sensitivity to light and signs of excessive tearing and redness. Cattle will blink frequently. Behavior also changes.

Cattle may seek shade and decrease feed intake. Once the disease progresses, cattlemen may see ulcers, cloudiness, swelling or rupture in the eye. Approximately 2 percent of pinkeye cases result in blindness.

Respond quickly with treatment

Infected animals should be isolated since pinkeye spreads quickly and is difficult to control. A long-acting antibiotic may be prescribed by your veterinarian to reduce the risk of transmission.

Other treatments may include an eye patch or the eyelid being sutured closed so the infected tissue can heal. This method makes the eye more comfortable and reduces further shedding of bacteria.

Prevention and, when necessary, treatment of pinkeye is critical to reduce the incidence of this costly disease.

Producers should consult with their veterinarian to discuss a sound prevention program and to ward off the spread of disease at the first signs of pinkeye.

With spring just around the corner, now is the time to prepare and prevent pinkeye in your herd.  end mark

References omitted due to space but are available upon request. Click here to email an editor.

Doug Scholz

Douglas Scholz
Director
Veterinary Services
Novartis Animal Health U.S. Inc.