Eye cancer, a tumour on the eyelid or eyeball, is the most common form of cancer in cattle, and in the early stages, can be misidentified as pink-eye.
These cancers are most commonly seen in Hereford or Poll Hereford cattle or white-faced Friesians and occur because of life-long exposure to sunlight.
Eye cancers may cause losses for producers due to condemnation at the abattoir and loss of potential production of affected stock.
The severity of eye cancers can be reduced by the early identification of growths and prompt action by either seeking veterinary treatment or culling. The incidence can be reduced by genetic selection.
The course of action that should be followed depends largely upon the size and severity of the cancer. Small eye cancers may be readily cured by prompt veterinary treatment.
However, if the owner elects to cull the affected animal, the following guidelines should be used:
- If the cancer is smaller than a five-cent piece, clean, and not flyblown, the animal can be sold through a saleyard for slaughter only.
- If the cancer is sized between a five and 20-cent piece, clean, and not flyblown, the animal can be sold directly to an abattoir only.
- If the cancer is bleeding, infected, flyblown or larger than a 20-cent piece, the animal should be immediately disposed of on-farm or via a knackery. Owners who fail to take reasonable action to prevent suffering may be considered for prosecution under the Prevention of Cruelty to Animals Act.