Beef Cattle

Don’t let pinkeye make you see red

As we approach the hot summer months, more and more producers are dealing with the nuisance of pink eye. Pink eye is a highly infectious bacterial disease. Although pink eye is nonfatal, it costs cattle producers more than $150 million per year. These expenses result from decreased weight gain, reduced milk production and treatment costs. Additionally, infected animals are worth less at sale. Pink eye is second only to scours/diarrhea in terms of diseases affecting calves.

Causes of pinkeye

While the bacteria Moraxella bovis is the main causative agent of pink eye, other microorganisms, such as Chlamydia, Mycoplasma and Acholeplasma, or viruses such as the IBR virus can either predispose the eye to pink eye or can make the disease more severe.

Pinkeye is a costly disease affecting cow/calf producers.

Pinkeye is a costly disease affecting cow/calf producers.

Irritants to the eye make it more susceptible to development of pink eye. These irritants include ultraviolet light, plants, dust and flies. Cattle that lack pigment around their eyes tend to be more susceptible to UV light irritation, resulting in inflammation and infection. Plants provide irritation though the release of pollen and chaff and also through physical irritation, such as poking, especially in the seedhead stage. Dust is not usually a major factor for pastured cattle and is more relevant for herds in confinement. Several species of flies — including face flies, stable flies and house flies — also serve as irritants and can actively carry the bacteria from animal to animal. Face flies have been shown to remain infected with M. bovis for up to 3 days after feeding on infected secretions. Pink eye can also spread via physical contact between animals, especially in close quarters.

If left untreated, ulcerations can occur due to pink eye and can result in loss of the eye. This is particularly troubling for bull calves, as bulls rely on visual cues to detect cows in heat. Research has also shown that weaning weights can be reduced by as much as 60 pounds per calf. Additionally, cattle with pink eye are discounted an average of $11.75 per CWT at the sale barn.

Fly control will help prevent flies from spreading pinkeye from animal to animal within the herd.

Fly control will help prevent flies from spreading pinkeye from animal to animal within the herd.


M. bovis is susceptible to many antibiotics, including oxytetracycline, penicillin and sulfonamides. Treatment involves handling cattle and either delivering an IM or SubQ injection or other direct eye treatments. As always, consult with your veterinarian prior to treatment. It bears mentioning that the new FSMA regulations will require these drugs to be prescribed by a veterinarian in the not-so-distant future. These drugs are available over the counter as it stands today.


Given that treatment is expensive, prevention is of the utmost important. The first step of prevention is to never bring infected animals to your farm in the first place, and this can be accomplished through careful inspection prior to purchase. Also, instituting a standard quarantine for new animals will help identify carriers and allow them to be treated prior to introduction into the main herd. Commercial vaccines are available — and you should always consult with your veterinarian before embarking on a vaccination program — but even vaccine manufacturers recommend environmental management and fly control in addition to vaccination. Other methods to help prevent pink eye include providing the proper mineral and vitamin nutrition, including adequate levels of zinc and vitamin A for eye integrity. Additionally, regular clipping of pastures will not only remove seedheads, which can irritate animals’ eyes, but will also increase the relative nutritional value of your pastures by increasing the vegetative growth. And finally, fly control will go a long way in keeping pink eye from spreading throughout your herd.

ULTRALYX<sup>®</sup> Rabon<sup>®</sup> Fly Control Blocks are highly palatable and can be placed directly on the ground, if desired.

ULTRALYX® Rabon® Fly Control Blocks are highly palatable and can be placed directly on the ground, if desired.

Feed through fly control

There are a variety of feed-through fly control options on the market today. These include Rabon® Oral Larvicide, Altosid® IGR and ClariFly®. A feed-through fly control interrupts the lifecycle of the target flies by passing through the digestive tract of the animal, allowing the compound to remain in the manure, where flies lay their eggs. However, Altosid IGR only prevents the horn fly, which is estimated to be the most economically detrimental fly, while Rabon and ClariFly also prevent horse, face and stable flies in addition to the horn fly.

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ULTRALYX offers a self-fed pressed block containing Rabon or ClariFly for your convenience. The ULTRALYX® Rabon® Fly Control Block and the ULTRALYX® ClariFly® Fly Control Block are compact and easy to use. Just place them where cattle congregate — no special feeders or bunks needed. Additionally, this block will deliver balanced levels of essential nutrients, including zinc and vitamin A, which are critically important for eye health. No additional salt or minerals are needed or recommended.

ClariFly and IGR options are available in a loose mineral form as well, including the Blueprint® High Mag Mineral with ClariFly®, which offers advanced trace mineral technology, or the ULTRALYX® 4% Phos with IGR Mineral. If you are looking for a low-moisture block option, check out the Blueprint® 6% Phos LMB Mineral Block with ClariFly® or the ULTRALYX® 20% Mag Fly Control LMB.


In summary, pink eye is a costly bacterial disease for the cow-calf producer. Anything that irritates or damages the eye makes it more susceptible to infection by the M. bovis bacterium. Treatment involves costly antibiotics and stressful cattle handling; as such, prevention is preferred. The prevention of pink eye can be achieved through a combination of vaccinations, management and fly control. ULTRALYX fly control blocks offer superior feed-through fly control, along with the proven intake and superior nutrition of ULTRALYX. 

Visit your local ULTRALYX dealer for more information on our available ULTRALYX products or call 1-888-718-3493 to speak to an ULTRALYX representative.


Rabon® is a registered trademark of Bayer Animal Health

Altosid® and ClariFly® are registered trademarks of Welmark International