Over the past five years, vet Stephen Ashdown has written many articles, spoken on equine matters and contributed widely to horse magazines.

Here he reproduces in the form of questions and answers about 100 topics, all of them common problems which afflict horses.

To access Topics click on Vet Advice Menu.

Is the Sun making him itchy?
Q My Arab gelding is suffering from a skin condition that I'm finding hard to control. It affects his legs, mainly on the cannon area, and is much worse on the leg with a white sock.

All I can describe it as is lumps or patches of off-white scum - a bit like a greasy residue that makes the hairs stick together. I have tried scraping the stuff off gently with my fingertips, but this just makes the area swell. I also wash his legs after work with Hexocil or baby shampoo, but it hasn't helped much.

He is constantly rubbing his muzzle up and down on the particularly affected white leg as though it is extremely itchy. He is also prone to sunburn on his muzzle.

Could the two problems be connected? Is there a supplement I can give him, or a product to wash his legs with that would solve the problem, or should I call out the vet?

A It is important that you contact your vet so that you can find out what's causing this troublesome condition. I think it's likely that your horse is suffering from some form of photosensitisation - particularly as the problem is worse on areas of pink skin.

Pink skin, usually seen under white patches of hair, on the muzzle and around the eyes, has less protection from the ultraviolet parts of sunlight than pigmented (dark) skin. Grease, lumps and crusts formed may well be all part of the body's reaction to UV light. Your vet should be able to help you discover exactly what is causing this sensitivity.

It could also be due to particular plants your horse is eating at pasture, or it could even be a form of liver disease. Until you get your horse over this problem, be extremely careful about allowing him out for too long in bright sunlight.

There are not many supplements that can help unless the exact cause of the condition is known. Dandelion roots may well help and milk thistle is also used to support the liver but are not as effective as more complex formulae.

More about Photosensitisation (2)

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