Caner Eye

General description
  • Eye cancers can occur in older cattle following prolonged exposure to sunlight.
  • Cattle with unpigmented eyelids and eyeballs are at most risk.
  • Elevated risk for developing eye cancers can be inherited.
  • Selection of resistant cattle (cattle with more eyelid pigment) is effective.
  • You should not breed from affected cattle.
  • Cancer eye is a painful condition.
  • Cattle with a poor prognosis should be sent for immediate slaughter if fit to travel.
  • Severely affected cattle that are unfit for travel should be immediately euthanised.
  • Affected carcases with evidence of spread of the cancer at meat inspection (enlarged lymph nodes that drain the head) are condemned.
  • Ultraviolet light exposure increases the risk of cancerous cell formation in the skin of the eyelid, third eyelid and sclera (junction between the whites of the eye and cornea).
  • Factors such as viruses, nutrition and pregnancy may also be risk factors for eye cancer.
Clinical signs
  • Cancer can develop after the emergence of protruding lesions around the eyelid, third-eyelid or sclera, but not all lesions will go on to become cancer.
  • If the lesion becomes cancerous, a spreading ulcer (erosion of tissue) will form. This can become infected, producing pain and result in weeping.
  • Eye cancers grow at different rates, but large cancers grow rapidly and often spread to internal organs. They can outgrow their blood supply resulting in a foul smell from the rotting core of the cancer.
  • They can take years to reach these final stages.
  • Affected cattle can become thin and weak, reflecting pain, difficulty seeing (if both eyes affected and/or internal spread of the cancer.
  • The presence of characteristic plaques or ulcers on the eyelid, third eyelid or sclera.
  • Small lesions can be surgically removed by a veterinarian. Suitable sedation and local anaesthesia may be necessary.
  • Lesions often recur, so treated cattle should be followed up and sent for salvage slaughter if evidence of recurrence is present.
  • Extensive and severe cancers can be removed by surgical removal of the eye by a veterinarian, but this is only warranted if there is no evidence of spread from the eye.
  • Severely affected cases should be immediately destroyed if they are in pain or are deemed not fit to travel for slaughter.
  • Breeding to select resistant cattle is the most suitable option for producers.
  • Susceptible stock should be examined regularly for early eye cancers, especially in the warmer months.
Learn more