When checking your cattle, it is good practice to be on the lookout for eye cancers.
An eye cancer is a tumour of the eyelid or eyeball.
It is seen most in white-faced cattle such as Herefords, and occur because of lifelong exposure to sunlight.
Eye cancers begin as a tiny growth and steadily increase in size. Eventually, the growth may invade surrounding tissues and spread to other parts of the body.
Therefore, eye cancers may cause losses to producers due to condemnation at the abattoir and loss of potential production of affected stock, plus the suffering of cattle if left unchecked.
The severity of eye cancers can be reduced through the early identification of growths and prompt action to treat or cull.
The incidence of eye cancers can be reduced by genetic selection by selecting for animals with pigmentation in the sclera ‘white’ of the eye and the eyelid.
When an eye cancer is detected 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 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, purulent (infected), flyblown or larger than a 20-cent piece the animal should be immediately disposed on farm or via a knackery. Owners who fail to take reasonable action to prevent suffering in their animals may be considered for prosecution under the Livestock Disease Control Act or the Prevention of Cruelty to Animals Act.
For further information, contact your local veterinarian or Agriculture Victoria veterinary or animal health officer, or in NSW your Local Land Services.
Dr Jeff Cave is an Agriculture Victoria senior veterinary officer.