Modern horse competition and racing are far removed from a horse’s natural environment. This, along with athletic training and high-starch diets, can lead to over-excitable behaviour in some horses.

This anxious behaviour can negatively affect performance and handling of horses. The many symptoms of over-excitability in horses are well recognised by horse owners and can include some of the following:

  • Hyperactivity
  • Over-reaction to environmental stimuli
  • Apprehensiveness or fearfulness
  • Inclination to flinch or spook
  • Lack of focus during competition or racing
  • Fractiousness
  • Resistance to riding

    • Furthermore some horses get stressed by particular situations such as loading into stalls or entering the competition arena. The causes of anxiety in horses are many and varied. Some of the predisposing dietary factors include:

  • High carbohydrate or sugar diets
  • Low pasture turnout
  • Hindgut acidosis
  • Nutritional imbalances

    • What you feed a horse can influence how the horse acts and changes to a horse’s diet can benefit some over excitable horses.

    CARBOHYDRATES

    The majority of high performance and racing horses are maintained on high carbohydrate diets which contain a large proportion of grain.

    Grain, particularly oats, is efficiently digested and absorbed from the horse’s small intestine, leading to a rapid rise in blood sugar levels. Overfeeding grain, and the resultant high blood sugar levels, can lead to nervous and jumpy behaviour in horses.

    One option to help calm a horse is an overall reduction in the total carbohydrate and therefore calorie intake. It is important to match the exercise levels of the horse to its calorie intake, as this ensures there is no excess of energy in the diet. Remember any calories or energy ingested by a horse must be expended in some form. Eliminating excess energy from the diet can reduce excitable behaviour.

    In some cases, however, a horse’s diet is not providing excess energy or calories. This is particularly the case for young horses, who need a high energy diet as they are still growing. In the case of over-excitable horses whose calorie intake must remain high, a switch to a diet that includes more oil may help.

    Oils are very high in calories and, when broken down by the body, they provide high levels of energy. However, oils are a ‘non-heating’ source of energy. One of the side benefits of this is that feeding oil does not increase the blood sugar levels. Changing an excitable horse from a high grain to a high oil-based diet can help improve behaviour.

    HINDGUT ACIDOSIS

    Hindgut acidosis is associated with apprehensive and nervous behaviour in horses. Horses predisposed to hindgut acidosis are typically on very high-grain diets. Not all the grain ingested can be digested in the small intestine, passing instead to the hindgut, where it unbalances the normal pH to an acidic environment. Acidity in the hindgut irritates the lining and can even lead to ulceration.

    This picture shows an equine stomach with mild ulceration (in yellow) and severe ulceration (circled in black). (Photo: Mark Johnston Racing)

    Because of this discomfort horses with hindgut acidosis can develop behavioural problems. The recommended dietary management of hindgut acidosis is to reduce the grain content of the diet and increase forage and pasture access.

    INCREASE TURNOUT

    The greatest incidence of behavioural problems occurs in horses that are confined to stables and fed large grain meals. Increasing turnout in performance horses and racehorses prone to behavioural problems has many benefits. While at pasture horses have the opportunity to graze, increasing the daily roughage intake. It also allows the horse to exercise freely and interact with other horses as an outlet for energy and natural behaviours.

    CALMING PRODUCTS

    There are many calming products offered on the market. Reputable nutritional supplements are a safe way to ensure all your horse’s nutrient requirements are met.

    Calming supplements aim to facilitate normal neurotransmitter levels, nerve conduction and muscle function, leading to a less anxious and more relaxed horse. Horse owners need to be vigilant in their choice of supplements. They should also be realistic about their expected results, as equine scientists are still debating their effectiveness.

    The causes of bad behaviour in horses are many, not just nutritional in origin. Managing unruly behaviour can be challenging and requires careful consideration of the training, management, husbandry and feeding of the animal to reduce the predisposing factors and improve behavioural outcomes.

    Restoring a horse’s composure and calmness can help their handling, performance and competition focus.

    Margaret Wilson BSc, MVB, MRCVS is Technical Manager at Foran Equine Products

    Web: foranequine.ie

    Tel: 01 626 8058