IT wasn't that long ago the choice of horse rugs was fairly simple. In winter, animals wore a tarpaulin-like New Zealand rug in the field and a jute rug or duvet-style Lavenham with a centre gerth strap in the stable at night.

To cool down after exercise you threw over the equine equivalent of a string vest. Racehorses and others in serious competition used a posh Newmarket striped travelling rug.

And that was that.

Horses were rugged up in the winter and once their summer coat had grown through, were turned out in the fields, naked as nature intended.

After all that was how it had always been done.

Twenty years ago, in fact probably more recently than that, it was almost unheard of for a horse or pony to routinely wear a rug in the field over the summer.

Not now.

A whole industry seems to have sprung up to provide summer coverings for equines. You now regularly see them bedecked in slightly curious garments aimed at protecting them from flies or harmful sun rays. Market a new fangled rug and someone, somewhere will buy it, often whether they really need it or not.

I have tended to be slightly sceptical about fly sheets on the basis that flies can get anywhere and if one crawls inside the head hood or underneath the body rug and then can't get out, it causes more problems than it solves.

If the fly problem is that bad for your horse, bring it into a stable during the day and let it out during the cool of the night.

However, last spring we had an experience with one of our horses that made me think twice about the winter rugged/summer not scenario.

It was late May, when admittedly the weather can still be changeable, but the horses had been out at night without rugs for three weeks and their summer coats were well grown through.

The weather forecast was for sunshine and showers, no problem with that. But there was the warning some might fall as snap hail storms, which they did.

Checking the horses that night, they seemed fine. The clouds had rolled by and although the animals were still damp, there was no obvious cause for concern.

But two days later we noticed the coat across the back of one of them was standing up and lumpy. A closer examination revealed a proliferation of tiny scabs spreading right from the base of the horse's neck to the top of its tail. It was a bad case of rain scald. The hail storm had literally scalded the animal's back. Obviously it had been standing with its rump to the storm and the hail had driven underneath the hair.

The other horse near it was completely unaffected.

Within days the condition of the horse's coat began to deteriorate. It became dry and dull and the scabs began to bleed.

The vet was called and treatment prescribed. But the seven-day course was only partially successful and at the end of it we still had a serious problem. "Try Camrosa," said the vet. "Can you give me any?" I asked. "No," he replied. "They advertise it in horse magazines."

So we bought some. It was not cheap, more than £30 for a "starter kit", which included the gel itself, before and after washes and a supply of surgical gloves to apply it. But it worked brilliantly. It did exactly what it said on the pot and within a week the scald had almost miraculously disappeared and the coat was growing back.

Which leads me back to the question of horse rugs.

In hindsight, I wished I'd had an unlined rain-proof rug to throw over the animal that day with the hail storms forecast. Not to keep it warm, but to protect from the hail.

The good news is that several manufacturers now make a rug that fits this bill. A tough, lightweight, water-proof rug that can be used as a turnout. As opposed to the things that keep you dry at shows between competitions and won't stand too much wear and tear.

This rug for all seasons philosophy can be carried a bit too far, but I am now convinced a summer rain sheet is a good thing.

And the cost is probably less than the vets' bills.