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Vincent Boureau's advices

Posted on: juin 6, 2019 | Author: Dr Vincent Boureau | Categories: Behaviour

« There are many ways to avoid the harmful consequences of excessive stress, sometimes called over-stress »

Vincent Boureau's advices

Nervous horse

In equestrian terms, having a nervous horse can mean faster responses, better impulses and increased speed. However, nervousness in sport horses can often negatively affect their performance. A working horse may get nervous for different reasons. Understanding these reasons is the first step to limiting the negative effects.

Stress and performance

Horses are a domesticated species that are today used mainly for their sporting prowess, although there are still many working horses around the world. However, in terms of animal behaviour, the basic patterns remain the same, such as social contact with other horses, herd instinct, and foddering. Sporting performance, whatever the discipline, generates both physical and psychological stress. At biological level, stress is caused by the activation of two complimentary pathways:

  • A nervous pathway: the sympathetic system is a division of the autonomic nervous system, i.e. it controls involuntary and unconscious actions, preparing the body to respond to stress by increasing heart rate, heightening the senses and accessing energy reserves. These actions result in visible signs known as neurovegetative signs.
  • A neurohormonal pathway: the secretion of stress neuromediators (adrenaline and noradrenaline) in the brain allows various organs to be activated hormonally, in particular via the secretion of cortisol into the bloodstream. Nervousness can therefore be identified 
  • neurovegetative signs: sweating, salivation, pale mucous membranes, rapid breathing, dilated pupils, increased heart rate, dilated blood vessels under the skin and repeated defecation.
  • behavioural signs: agitation, grinding teeth, hypersensitivity, hyper-reactivity.

The stress response is therefore both physiological and behavioural. However, as long as it does not exceed the horse’s capacity for adaptation, stress is not incompatible with performance.

Equine cognitive capacities

Horses are intelligent creatures with a particularly keen sense of vision, hearing, smell, touch and taste, allowing them to perceive their environment in great detail. In any given situation, they can process the sensory input, memorise the experience and become accustomed to it. Nevertheless, in stressful situations, horses, which are a prey animal, will react rather than think. Their memory is more photographic than dynamic.

Their emotional response overrides their learned response, triggering their inbuilt and self-preserving reflex of flight.

This brain function forms part of the learning process. It is therefore easy to see how a change, even a small one, in the horse’s usual environment or situation can disrupt its emotional balance to the point that it forgets what it has learned through experience and resorts to its flight instinct.

Exceeding the capacity for adaptation and well-being

Different factors can lead a horse to exceed its cognitive thresholds and ability to adapt to a situation, in particular fear and a restive nature. Faced with a scary situation, the horse, a prey animal, will innately react by fleeing. If flight is not possible, the fear will persist and produce visible invasive signs of nervousness. The neurobiological effects of fear can annihilate all learning and memory processes in horses at work. A restive nature in a working horse will manifest as avoidance behaviours, ranging from simple defensive actions to aggression. This learned behaviour could be:

  • a behavioural manifestation of pain: sudden and unusual nervousness in an animal that usually performs well could be indicative of pain.
  • incorrect training techniques: The learning process in horses, as in many domesticated species, is based on the principle of operant conditioning. The appropriate use of positive reinforcement (rewards) and negative reinforcement (removing a stimulus) forms the basis of horse training and allows the horse to remember what it has learnt. However, the use of punishment without any context, e.g. too long after the undesired behaviour can lead to deviant behaviour and nervousness.

Nervousness in sport horses can therefore be a symptom of an emotional conflict, due either to a physical problem such as pain, or the incorrect use of training techniques.

How to improve quality of life for performance horses

There are many ways to avoid the harmful consequences of excessive stress, sometimes called over-stress:

  • Food is the primary motivation for horses which, in a natural environment, will spend 60% of their time grazing. Choosing a feed that takes longer to eat and makes the animal feel full for longer, rather than a feed that provides a one-off energy "high”, will improve quality of life for sport horses. Poor feeding can trigger stress and behavioural issues.
  • Being able to socialise with other horses is one of the main ways in which these animals can cope with the huge psychological pressures of their work. Social isolation can cause aggression.
  • Horses can gain stimulation from both their environment (stables should be designed to promote outside contact) and regular exercise. Under-stimulation is a predictive factor of abnormal behaviour, in particular stereotypies.
  • Making sure that training techniques are correctly applied will build a positive relationship between rider and horse. Daily grooming and positive interactions outside the working environment all improve well-being.

Stress is a part of life for sport horses. It helps them adapt and respond effectively to changes in their environment. Exceeding the animal's tolerance threshold will lead to excessive nervousness and will undermine both performance and quality of life for sport horses. Finding the right balance is a skill.