Like most types of cancer, early detection leads to better outcomes.
What is cancer eye?
We see a lot of cancer eye (otherwise known as squamous cell carcinoma). As the name suggests, it's a cancer of the eye, which can affect the eyelids, eyeball or 'third eyelid' (the eyelid that slides across the eye) and it is as bad as it sounds.
Why do cows get it?
Environmental, viral and genetic factors are said to play a role in this tumour's development. It is most commonly seen in unpigmented tissue (commonly white-faced animals, but it is not just localised to these) and is related to ultraviolet radiation - not too dissimilar to skin cancer in humans.
What does it look like?
The initial stages of cancer eye are usually slow. It may just present as a tiny, knobbly growth on the third eyelid, which can be hard to detect. Cows may have a slight discharge from the eye, due to irritation.
Over time, the tumour will (usually) continue to grow in size, eventually becoming a large mass that becomes necrotic and foul smelling.
If the tumour spreads, it can also cause the lymph nodes around the cow's head to swell up.
What should you do about it?
Quite often, people initially confuse cancer eye with pink eye and treat it with a tube of eye ointment, which will offer no improvement. After this, a vet visit is highly recommended.
Like most types of cancer, early detection leads to better outcomes. Early surgical removal of the lesion provides the best outcome and the prognosis is a lot better when the lesion is small in size, as we are able to get good margins. A cell left behind is enough to seed another tumour!
Sometimes, just the third eyelid can be removed, while other times, the whole eye might need to come out. In some cases, nothing can be done and calling pet food is the only option left.
If the tumour has invaded local lymph nodes, or has migrated into tissues around the eye, then removal is not an option.
Be aware that transportation to the works is not permitted when she has reached this stage. Only a very small cancer eye is allowed, if certified by a vet.
We cannot write a works certificate if she is presented like this, with the issue being compromised animal welfare. A blown out eye leaking pus and rotting is obviously very painful and one that we aim not to have on-farm.
It pays to check!
When you’re working at the back-end of a cow everyday, it’s easy to miss what’s going on at the front-end, but, it should be good stockmanship and practice to check periodically.
Stages of development:
Early stages of cancer eye, as above, can be easily removed and are less likely to recur.
This can be removed, however, the chance of recurrence is high.
During pregnancy testing, our techs quite often pick up cases of cancer eye and notify us.
If you see a tumour in your herd, get it checked! Even if you just flick your KeyVet a photo, we can usually give you an indication as to whether it needs to be examined more closely, or removed, leading to a much better outcome for all!
If in doubt, get it checked out!
