Melanoma outlook
Q: I have found a 10-year-old grey mare who I would like to buy, but she has a melanoma on the underside of her dock. The owner says it hasn't altered in the two years she's owned her but I would appreciate some advice about melanomas to supplement what my vet has already told me.

A: Melanomas are relatively common tumours made up of cells in the skin, which produce the pigment called melanin. They are particularly common in grey horses and often cause no problem. There is however always the danger that such lumps will become cancerous.
The reason this happens is not always clear, but it is normally related to a weakening of the horse's immune system. Tumour cells of all kinds are abnormal cells and the body naturally tries to destroy them, but it is often not strong enough to do so quickly.

Keeping any horse as healthy as possible will help to maintain a strong immune system. Feeding is the most important factor, but I am afraid that feeding horses for a strong immune system as nature intended is not easy. A natural diet comes from a large grazing area with access to a large variety of different plants growing on different soil types.

In an artificial environment, we supplement the horses grazing with concentrates and supplements know to boost the immune system in order to make up for any deficiencies that might exist in his diet.

For long term supplementation, I would recommend as good a vitamin and mineral supplement as you can afford plus a little seaweed for a few months each year and the use of selected herbal formulae.

I would be wary of Echinacea-based products because these are not suitable for long term support of the immune system and are better used when specific infections are known to be near at hand or have just started to cause problems.

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