It depends on rather a lot of things. Some horses are naturally excitable or nervous because they were born that way, and changing their feed will not turn them into docile, laid-back characters. Other horses become too full of themselves because of the way they are managed, for example if they get little or no turnout. Once again buying a 'non-heating' feed will not solve the basic problem.

Other factors that need to be considered include the level of fitness of the horse. An unfit event horse starting on walk work might be quite a relaxed ride, but the same horse several months later, when it is very fit, is likely to be much more amusing to hack out. When and how your horse becomes too much of a handful also needs to be considered. Often the answer lies in schooling or discipline rather than feeding.

Another important factor is the feed itself. The term 'non-heating' is used nowadays by feed manufacturers to indicate that the feed so described will not adversely affect temperament. It is an odd expression because it has nothing to do with the warming effect of fibrous feeds (feeding hay, for example, literally warms a horse internally because of the heat of fermentation in the hindgut). The use of 'non-heating' was probably derived from expressions like 'will not hot a horse up' or 'will not make a horse too hot to handle'. It has to be said that some feeds are more deserving of this description than others.

1) Overfeeding cereals and other starchy feeds.

We all know that horses evolved to graze for about sixteen hours a day and that their digestive systems are therefore designed for 'trickle' or 'little and often' feeding of forage. Many horses have a calmer temperament when they are living out than when they are stabled. One of the contributing factors for this can be the way they are fed. When hay or haylage alone will not meet the energy requirements of the horse the traditional solution is to provide the extra energy in the form of cereals or compound feed If horses are given large feeds of cereals or cereal-based compounds their digestive system can struggle to cope. Excess starch can overflow from the foregut into the hindgut and upset the microbial balance. This in turn affects the acidity of the hindgut and, in ways that are not fully understood, can affect a horse's temperament. Over feeding energy simply makes some horses fat and has no effect on their temperament whereas other horses become very high-spirited. Thoroughbred types are more prone to react this way than warm-bloods or native ponies but there are plenty of exceptions.

2) Feeding cereals and other starchy feeds can result in a short-term energy boost.

Many horse owners report that their horses become unmanageable when fed even small feeds of cereals or cereal-based compound feeds and this is probably due to the rapid rise in blood sugar levels after a feed containing fast-releasing energy. The raised sugar levels will provide a boost in energy. The cereal most often quoted as causing a problem is oats, which puzzles nutritionists as, by looking at their analysis, they are the least likely cereal to have a 'heating' effect on horses. Over the years various theories have been put forward as to why oats, rather than barley or maize, should make some horses high-spirited but non are entirely convincing.

It is partly because oats made some horses 'too hot' that the first 'non-heating' cubes came on the market. They were made without oats and were often formulated to a slightly lower energy level but otherwise were similar to the standard cube. Over the years the demand for this type of product has grown enormously and there is now a huge variety of 'cool' and 'non-heating' feeds on the market. Some of these feeds are now very sophisticated compared to the early 'non-heating' products and the cubed products may well help to maintain a calm temperament in horses which react adversely to high starch feeds. The starch levels in 'non-heating' cubes are about 10-15%.

'Cool' mixes, however, by their very nature, usually contain rolled or flaked barley, flaked maize and flaked peas. They are often molassed and contain about 25% starch. I can see no sensible reason for buying them unless your horse reacts only to oats and is otherwise perfectly calm when fed sugary/starchy feeds.

The form in which energy is provided in a feed can clearly influence the temperament of some horses. We have discussed how starches, found in high levels in cereals, provide fast-releasing energy; and sugar, commonly found in horse feeds as molasses, is one of the fastest-releasing energy sources of all. If you try a new feed in the spring and think it has made your horse fizzy, don't forget that spring grass contains very high levels of sugar and is more likely to be the cause.

On the other hand, digestible fibre, found in high levels in feeds such as hay, haylage, alfalfa and unmolassed beet pulp provides mainly slow-releasing energy. Oil is rightly becoming an increasingly popular feed for horses as it provides high levels of energy but in a slow-releasing form. This makes it a very useful product when we are trying to increase the energy intake of high-spirited horses.

A common-sense approach to feeding horses with nutritionally related temperament problems.

· Provide as much of the feed as possible in the form of forage. The higher the forage to concentrate ratio, the closer you get to the horses natural way of feeding and the calmer he will be. The general advice would be to buy the best quality available in order to reduce reliance on hard feed but some horses become difficult to handle on early-cut haylage and you may need to downgrade to later cut haylage or hay. (Should your horse be full of beans and a very good-doer you may need to restrict hay intake and feed a mixed hi-fi chop with a low sugar dressing to maintain fibre intake)

· Feed a balancer or, if your horse is a very good-doer, a fully comprehensive supplement. Both these products will provide the micronutrients needed to balance forage and allow the horse to get the maximum benefit from it. This will reduce the need for hard feeds. Look out for a balancer that features several factors to help calm temperament in responsive horses. A cereal-free balancer would be ideal.

· Feed probiotics, as these will create optimum conditions in the hindgut for fibre digestion and, once again, help the horse to gain more benefit from his forage. There is a lot of anecdotal evidence that feeding probiotics, either on their own, or incorporated into a feed balancer or supplement, can calm certain horses and ponies.

· If more energy is required in the feed look first to medium-energy, high-fibre feeds in place of cereals or compounds. There is a wonderful choice nowadays but products like alfalfa (in chop or pellet form) or unmolassed sugar beet pulp (or if your horse finds this unpalatable use well-soaked sugar beet pulp but discard the juice, which is where most of the sugar will be) are ideal.

· If still more energy is required, for either work or weight gain, look to oil. Soya or corn oil is ideal for horses and you can feed much more than a tablespoon! For example, a 15.2hh show hack could be fed as much as 450ml daily providing it was divided into at least three feeds. Contact a nutritionist for individual advice on this as you will also need to ensure that your horse has an adequate intake of anti-oxidants e.g. vitamin E and selenium if you are feeding high levels of oil.

· If you horse will not eat much oil, or if despite offering oil your horse still needs a higher energy intake, try a 'non-heating' high-fibre cube or a little micronised barley. · All the above feeds should be fed little and often, to copy nature and avoid starch overload.

· Do not feed coarse mixes unless your horse's problem is only related to oats. · Avoid molasses.

· Avoid all cereals except micronised barley as this has been scientifically proven to be the best-digested cereal.

· Ask a nutritionist for individual advice because many of my comments, for reasons of space, are generalizations.

· Don't be afraid to ask feed companies for detailed information about their feeds to help you make an informed choice. If they will not answer reasonable questions about their products, for example the level of vitamin B1, then buy from a firm that will!

Nicola Tyler B.Sc. (Hons) TopSpec Equine
Advice Line: 01270-624095 Products produced by TopSpec Equine that are suitable for feeding to high-spirited horses are :-

TopSpec Feed Balancer TopSpec.comprehensive supplement
TopSpec No:1 Healthy Hoof supplement
TopSpec No:2 Leisure Horse and Pony supplement
TopSpec No:3 Broodmare and Youngstock supplement