Pink Eye in Cattle

IBK-Infectious Bovine Keratoconjunctivitis

Pink eye is a painful and highly infectious eye disease of cattle which if not treated adequately can result in large numbers of animals affected and temporary or permanent blindness.


The primary cause of pinkeye is bacteria known as Moraxella bovis, but other bacteria and viruses are often involved. The high risk period is late spring and summer. Pink eye occurs predominantly in young cattle, but cattle of any age can be affected.


Risk factors

Risk factors for pinkeye include wind, dust, flies, stalky vegetation and high stocking rate. Damage to the surface of the eye (scratching from grass seed heads) and ultraviolet radiation can predispose the eye to infection. The bacteria can be present on flies and grass seed heads. Forcing cattle to graze low in stalky feed is a high risk for pinkeye.


Clinical signs

The first signs of pinkeye are weepy eyes. A central ulcer soon develops followed by cloudiness in the eye. If left untreated, this ulcer enlarges and pus forms in the eye leading to increased pressure and eventual rupture of the eye in extreme cases. Pink eye can cause prolonged and serious pain.


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The Impact

Pink eye is an animal welfare issue causing prolonged and serious pain.

Consequences of pinkeye include:

  • depressed growth rates
  • loss or culling because of eye rupture and permanent blindness
  • disruption to seasonal grazing management
  • veterinary and labour costs to treat infected animals
  • lowered sale value of animals with eye lesions (weaner cattle)
  • Prolonged infection in an infected mob for 3-5 weeks.

The disease may exist for 3-5 weeks in some individuals, with a peak in a mob of about 3-4 weeks.

Despite this many farmers believe Pinkeye is not a significant problem and many choose to not treat or prevent the disease and let the disease take its course.

Diagnosis is made by clinical signs and in some cases swabs obtained from infected eyes. A veterinarian examination is required to confirm pinkeye.

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Management and control

Quick action is required to prevent the spread of pinkeye. Affected animals should be immediately removed from the mob for treatment. Infected animals must remain separated.

Antibiotic treatments are commonly used to treat pinkeye. These will be prescribed by your vet who will also show you how to treat animals, and decide if the whole mob should be treated.

Surgery to either protect they eye with the third eyelid, or close the eye completely is possible.



A vaccine is available which is most effective if given 2-3 weeks prior to the expected pink eye season. It is less effective if given once the pinkeye has started. Grazing management, stocking rate, and animal wellness are all very important aspects of pinkeye prevention.



Contact your nearest VetEnt clinic to learn more about risk management of Pinkeye in your herd.

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Pink eye is a painful and highly infectious eye disease of cattle which if not treated adequately can result in large numbers of animals affected and temporary or permanent blindness.