How to Heal Pink Eye in Livestock

Updated Dec 8, 2025

Although pink eye is a relatively benign disease in humans, the U.S. beef industry experiences an annual loss of $150 million due to pink eye in cows. 

Pink eye is both painful and potentially devastating if it spreads to the entire herd.

Thankfully, antibiotics can treat pink eye. Keep reading to learn more about pink eye in cows, including how to identify it, treat it, and prevent it.

What Is Pink Eye in Cows?

Pink eye, also called infectious bovine keratoconjunctivitis (IBK), is an eye infection that causes redness, tearing, and discomfort in cattle and other livestock. As the name suggests, pink eye is an acute and contagious ocular disease that causes redness and irritation.

A pink eye infection can last for several weeks and affect one or both eyes. In severe cases, pink eye can cause corneal ulcers and scarring that can result in blindness.² Pink eye spreads quickly through a herd because it’s highly contagious. Flies, shared feed, and close animal contact make it easy for the bacteria to move from one animal to another.

How Do I Know If My Livestock Has Pink Eye?

There are many detectable symptoms of pink eye that can help to diagnose the disease before it progresses or spreads further in the herd.

Common symptoms include:

• Conjunctivitis – Redness is the first telltale sign of irritation.
• Tears and runny eyes – Tearing is an obvious sign of pink eye because dirt will stick to the tears. This is especially noticeable in light-colored cattle. 
• Squinting and behavioral changes – The sensitivity to light caused by pink eye can produce obvious symptoms like squinting, but it might also cause more subtle behavior like spending extended periods in shaded areas or keeping the eye shut.²
• Ruptures – Ruptures result from the increased pressure in the eye due to inflammation.
• Decreased appetite – If your cattle have decreased vision or pain, they might struggle to find their food and water, resulting in dehydration and weight loss

There is no standard window from when pink eye in cows becomes noticeable to when it becomes a serious threat.

However, it is vital to identify and treat pink eye as soon as possible to prevent its spread among the herd and more serious consequences like blindness.

What Causes Pink Eye in Livestock?

Pink eye in livestock doesn’t have just one cause; it usually develops from a mix of factors working together. Because there isn’t just one cause, it’s important to recognize the different conditions that can set the stage for pink eye.

#1 Infectious Agents

Moraxella bovis (M. bovis) is the leading cause of pink eye infections in cattle. Hair-like structures called pili cover this bacterium and attach to the cornea. Therefore, it’s not washed away through normal tearing.

In positive pink eye cases, both ocular and nasal secretions will contain this organism.

Mycoplasma, Chlamydia, and Infectious Bovine Rhinotracheitis (IBR) are other organisms that cause pink eye infections. The transmission occurs through direct contact with:

• Other infected animals
• Flies
• Inanimate objects like instruments and halters²

There are typically multiple subtypes of bacteria like M. bovis within one infected animal, so it can be challenging to choose the proper treatment.⁵

#2 Environmental Causes 

Environmental irritants can either predispose your cattle to pink eye or exacerbate the disease. 

Examples include:

• Excessive sunlight
• Dust
• Grasses
• Pollen 
• Flies

Sunlight and dust can irritate the eyes while tall plants like grass and weeds can scratch them.³

Certain feeding practices can also irritate the eyes, including eating hay from the middle of a round bale or from overhead feeders.²

#3 Animal Causes 

Flies contribute to pink eye both indirectly and directly.²

• Indirectly, flies create irritation and inflammation, increasing the likelihood of pink eye in cows.
• Directly, flies feed on the eye secretions of cattle and transmit M. bovis or other infectious agents. 

#4 Breed

The breed of your cattle also affects their chance of contracting pink eye. Brahman or Brahman-influenced cattle have a greater resistance to developing pink eye.

On the other hand, breeds like the Hereford and Charolais cattle can be more sensitive to UV light and inflammation because of a lack of pigment around their eyes.²

How to Treat Pink Eye in Livestock

Treatment of pink eye in cows can be a multistep process. It is crucial to begin treatment as early as possible before the disease progresses and causes permanent damage. With prompt treatment, most animals show improvement within 7–10 days, although severe infections can persist for several weeks.

#1 Antibiotics

Antibiotics are often the first line of treatment for pink eye in cows. The type of antibiotic will depend on the infectious agent and the overall situation with the herd. 

Some options include:

• Oxytetracycline and Penicillin – These antibiotics can treat the M. bovis organism that causes most pink eye infections.
• Long-acting Oxytetracycline Injections – The efficacy of these injections increases when treatment occurs early in the progression of the infection. If a large number of animals are infected, veterinarians often combine oxytetracycline injections with medicated tetracycline feeds.  
• Penicillin Injections – Penicillin can be injected under the thin membrane of the eye, the conjunctiva. This method is very effective but requires better animal restraints and more labor.

Regardless of which antibiotics your veterinarian recommends, it is crucial to follow the labeled dose and route of administration and complete the entire course of treatment. While mild cases sometimes clear up on their own, leaving pink eye untreated risks permanent eye damage or blindness, so veterinary treatment is strongly recommended.

If your herd has a large number of pink eye cases that are resistant to standard treatment, you should contact your veterinarian as soon as possible. 

Causes of treatment-resistant infections include multiple organisms and altered antimicrobial sensitivity. Your veterinarian can establish these antimicrobial sensitivity patterns and determine a more specific treatment plan.²

#2 Sprays and Ointments

There are many approved sprays and ointments that can treat pink eye. Usually, you will apply them daily. Ensure that you spray the eye close-up because cattle may blink or turn away if you spray from a distance.

A study by Auburn University found that the Vetericyn Plus™ Pinkeye Spray effectively reduced both pink eye infections and resulting pain.

The group of cows who received the Vetericyn Plus™ Pinkeye Spray experienced an average 79.1% reduction in their pain score on day two and an 83.7% reduction in pain by day ten of the trial. The control group only had an average decrease in pain of 18.3% and 67.9% respectively.

As more public pressure and legislation require reductions in antibiotic use in food-producing livestock like cattle, non-antibiotic options like the Vetericyn Plus™ Pinkeye Spray will become essential.⁴

#3 Eye Patches or Coverings

Many veterinarians recommend eye patches or coverings. Applying a patch over the infected eye will protect it from further irritation and help prevent the spread of pink eye among the herd by blocking flies from feeding on the infectious secretions.  

An eye patch will also reduce irritants including sunlight, which is incredibly important during the healing process.³ Ultraviolet rays from the sun can activate enzymes that will increase the potential damage to the eye if the M. bovis bacteria is the cause of the infection.⁵

#4 Surgery

If the case of pink eye is especially severe, surgery might be necessary. A veterinarian can complete a third eyelid flap or suture the eyelids closed to protect the eye if the animal has severe corneal ulcers.²

Best Practices for Treating Pink Eye

The severity of the pink eye infection determines the recovery time. Healthy animals respond well to early treatment interventions while immunocompromised animals will not respond as well.³

If you examine a cow with potential pink eye, use disposable gloves and throw them away between each animal to decrease transmission. You should also disinfect equipment like halters and nose tongs that come in contact with infected secretions and isolate infected animals.²

How to Prevent Pink Eye in Livestock

Prevention is the best medicine. Reducing fly populations, keeping pens clean, and providing shade are some of the most effective ways to prevent pink eye in livestock. Since pink eye in cows is a multifactorial disease, it’s best to utilize multiple preventative measures, including:

• Vaccines – You can vaccinate your cattle for viruses that cause pink eye or increase the severity including infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea (BVD). Unfortunately, because M. bovis has multiple types and subtypes, vaccines are only effective for certain strains. Additionally, it takes two doses and several weeks to develop full immunity, so an animal can still become infected immediately after their vaccination.
• Nutrition – Correct nutrition can prevent your herd from developing pink eye by ensuring their immune systems function properly.
• Fly Control – Fly control to reduce the spread of pink eye can include insecticide sprays, special ear tags, and cattle rubs. In addition, clean areas of stagnant water and manure piles where flies reproduce.
• Environmental Control – Trim your pastures so cattle don’t encounter physical irritants like tall grass. Likewise, provide areas for shade so your herd can avoid excessive direct sunlight.³

Keep an Eye Out for Vetericyn

Preventing pink eye in cows and providing early treatment will protect your revenues and prevent unnecessary pain and injury to your livestock. Prioritizing livestock care is essential to keeping your herd healthy and thriving.

You care about your herd. So do we. 

At Vetericyn, we care about the health of your Livestock. Check out our blog on Vetericyn to read more on animal care and upkeep. Questions regarding naval infections or mastitis in goats? We’ve got you covered. Vetericyn’s animal wellness products like our Vetericyn Plus® Antimicrobial Eye Wash and Antimicrobial Pink Eye Spray will help ensure your herd’s long-term health and comfort. 

Reviewed by Dr. Kathy Adamson

Dr. Kathy Adamson earned her bachelor's degree from the University of Notre Dame and her Doctor of Veterinary Medicine degree from the University of Wisconsin-Madison School of Veterinary Medicine.

She completed a one-year small animal medicine and surgery internship at the North Carolina State College of Veterinary Medicine. Alongside her studies, Kathy worked in a research lab, contributing as an author and co-author to various journal articles.

She has also pursued medical writing and editing certification through the University of Chicago Graham School. Currently, she runs KMA Veterinary & Medical Writing, a freelance medical writing company, serves as the Digital Content Manager for the Greater Chicago Area Chapter of the American Medical Writers Association, is a member of the AMWA Communications Committee, and enjoys writing about healthcare topics for people and their cherished pets.

Sources:

1. National Library of Medicine. Genetic parameters of infectious bovine keratoconjunctivitis and its relationship with weight and parasite infestations in Australian tropical Bos taurus cattle. https://pmc.ncbi.nlm.nih.gov/articles/PMC3517348/ 
2. The Cattle Site. Pinkeye in Cattle: Treatment, Prevention and Control. https://www.thecattlesite.com/articles/3922/pinkeye-in-cattle-treatment-prevention-and-control/#:~:text=Treatment%20of%20Pinkeye&text=bovis%20organism%20is%20sensitive%20to,combination%20with%20medicated%20tetracycline%20feeds 
3. Kansas State University. Pink Eye in Cattle. https://www.johnson.k-state.edu/crops-livestock/agent-articles/pink-eye-in-cattle.html 
4. American Association of Bovine Practitioners. Clinical evaluation of Vetericyn Plus™ Pinkeye Spray. https://journals.tdl.org/bovine/index.php/AABP/article/view/3542
5. Beef Magazine. How To Prevent & Treat Pinkeye In Cattle. https://www.beefmagazine.com/health/vets-opinion/busting-pinkeye-in-cattle-0401