We often read about the importance of breeding horses with a good temperament but what do we mean by temperament, is it something that can be measured and can a good or bad temperament be inherited?
Traditionally horse breeding has focused on the horse’s morphology or conformation, specific breed characteristics and on certain performance- success criteria. However, over recent years we have seen the addition of a number of more behavioural based characteristics playing a role in different stud management/selection programmes – Characteristics such as ‘rideability’ or ‘trainability’ are used in the grading of some warmblood stallions. This is interesting because it assumes that we know that these traits can be measured accurately and meaningfully and that there is a genetic component to them.
In human literature, temperament describes a person’s nature or their personality. The characteristics possessed by an individual which uniquely influence their emotional, behavioural and motivational responses to various situations. When we talk about human personality we often categorize people in ways that are universally understandable, such as those who we describe as ‘worriers’, ‘ambitious’ and ‘sensitive’. Human personality research has a long history and there are a variety of theories and models as well as personality tests. This area of study has been applied in a variety of circumstances including during the hiring process, trying to determine if a person has the right temperament traits to succeed within a given role.
Temperament is a term commonly used to describe a horse’s ‘personality’, emotionality or reactivity. It is usual amongst horse owners, to refer to a horse as having a certain type of temperament and it is usually assumed that temperament is something that can be inherited. Indeed horses appear to be selected (or avoided) for breeding at least partially on the basis of their temperament. However, despite this apparent acceptance, there is little empirical evidence to support the notion that temperament is something passed onto a foal, and it is only relatively recently that equine researchers have become interested in determining whether horse temperament is a measurable and heritable property.
In horses, as with other animals, the main body of research has related to working out how we can effectively measure individual differences between animals and how this influences responses to stressful or fear provoking situations, learning events and survival. An individual horse’s distinctiveness can be described in terms of a variety of behavioural traits – consistent behaviours that occur together in one animal that can be used to predict the way that animal will behave in a given situation. The main premise is that temperament is expressed early in development and remains relatively consistent over the horse’s lifetime. In horse’s this has been dubbed ‘Horsonality’ by Dr Visser, one of the influential behaviour researchers in this area of equine science. This is an important area of study especially when you consider the alarming increase in the number of serious accidents with horses in sports as well as in leisure and the fact that many rider and handler accidents are often caused by characteristic behaviours of the horse.
One of the main questions considered by human psychologists is whether personality is mainly genetically inherited or if it develops gradually during lifetime through experience? The ‘Nature vs Nurture’ debate has led to some interesting research. Early studies of humans focused on the amount of variation in personality that could be explained by genes through examining personality similarity between twin pairs. A heritability score of 1.00 or 100% would mean that all variance is genetic. The results showed that for identical twins who share the same genetic make-up, heritability estimates hovered around 46%, with 23% for fraternal twins (who share roughly 50% of their genes). However it is thought highly unlikely that there are specific genes controlling personality – rather that we inherit a set of genetic predispositions or ‘preferences’, which if the correct environmental circumstances are present, will be triggered in certain ways leading to an individual behavioural response. In recent studies of birds involving fostering of the young chick before they have had parental experience (in this case before hatching), researchers have found that the behaviour of the foster parents has a much greater impact on personality and individual choices than the genes inherited from the parents.
Horse research is certainly less advanced when it comes to uncovering the nature/nuture aspects of a horse’s character. So far, much of the equine research has included the development and use of behavioural tests as well as observer/rider/handler assessment scoring systems, often related to a limited number of traits of interest to the study group. The behavioural tests carried out under controlled conditions, tend to focus on what is variously described by the researchers as; fearfulness, flightiness or activity as shown by an individual in response to potentially frightening stimuli presented to horses when they are in an enclosed environment, and measuring their willingness to approach the unfamiliar object, human or space as well as their general behaviour, such as flight response time, amount of movement around the arena, vocalizing and even some physiological measures such as heart-rate and stress hormones.
Yet, despite the obvious importance of understanding and describing personality traits in horses and the wealth of studies by various authors attempting to find ways of measuring variation in horse responses, there is still as yet, no agreed clear way to assess a horse’s temperament. Studies have shown that traits such as; flightiness, trainability, socialness and willingness to perform, can be defined and measured in ‘one-off’ tests of horses, but in most cases there is little evidence of repeatability and often there are differences between studies in agreement on what is meant by each personality trait. In the Netherlands, Kathalijne Visser’s work has involved longer term studies, some lasting for over four years. During this research she has tested the various responses of large numbers of young Dutch Warmblood mares and geldings, of known breeding and then followed their development as they progressed through performance testing, training and finally to their new homes. Visser has concluded that in order to get a full picture of the horse’s temperament, the horse needs to be challenged in many different ways and measurements need to be made more than once. In her behavioural tests she subjected the young horses to various unfamiliar experiences, including; ramp-climbing, fear tests, learning challenges and interactions with humans, and then monitored their immediate and longer term responses. Her work has shown that it is possible through meticulous recording of behavioural responses under controlled conditions during early life, to predict a horse’s success in various roles following training. She has shown that the temperament traits she has identified in horses using behavioural tests, are related to the horses’ responses as rated by riders unfamiliar with them.
The idea of using a simple test early in a horse’s life to determine its personality type, or temperament, is certainly attractive and there is considerable potential for a testing scheme/programme, if a reliable set of tests was to be developed. If tests were reliable predictors of horse behavioural responses, the suitability of a horse for certain kind of work, a method of training, a particular discipline, and a certain living environment, could all be assessed early in life. This would allow a matching of horses for specific roles/sports and avoid the wasting of time, energy and money on rearing and training horses that were not suited to a particular task as well as helping to prevent the development of unwelcome behaviours as well as welfare issues where horses and riders are incompatible or where expectations are not met. However, to be useful, tests of learning ability must relate in some way to the horse’s trainability, and tests of fearfulness should relate to the horse’s ability to cope with new challenges. In addition, in order to be of practical use such behavioural tests need to be vastly simplified, without compromising their reliability to allow rapid assessment of a large number of horses.
Interestingly, although horse-owners and riders speak freely about temperament and they assume that others understand what is meant by subjective terms they use to describe their horses, there appears to be little evidence of universal agreement. When testing the reliability of labels often used for horses, such as stubborn, laid back, and flighty, researchers from Lincoln University showed that when a number of experienced horse trainers were asked to describe the same horses, they did not consistently agree with each other in their assessments, apart from when horses were described as ‘flighty’ or ‘sharp’. In a further study in the Netherlands, researchers in Dr Visser’s Laboratory discovered that when riders were asked to score unfamiliar horses, only two criteria of the many that were used by riders; ‘responsiveness to the environment’ and ‘attention to the rider’ were reliably agreed upon. These results are worrying especially where horses are ridden by a number of people, since they could be ‘labelled’ by one trainer/rider early on in life, and any consequent training and handling techniques may be influenced by this assessment. Almost becoming a self-fulfilling prophecy.
In terms of application of temperament studies, there are some reports describing the relationship between certain temperament traits such as emotionality (or nervousness) and the ability of a horse to learn new things. Horses described as highly reactive, have higher overall activity when placed in new situations and also have higher heart –rates when exposed to something novel, as compared with the less reactive horses. These more nervy horses have been shown to be poor learners, who need more time and careful handling to enable them to reach their potential. This can probably be explained by the fact that we know that fearful horses are highly motivated to escape or avoid unfamiliar circumstances, and so will be less attentive when it comes to training new behaviours. Interestingly these more nervous horses, are most likely to be problematic to train, probably showing more conflict or stress behaviours and they have the potential to be labelled as difficult with the various possible consequences. Yet with careful temperament testing it might be possible to identify these types of horses early in life and to provide the appropriate learning environment to ensure their successful training.
Further research has also investigated the heritability of susceptibility to develop stereotypic behaviours such as crib-biting and weaving. Certain breeds of horse have been shown to be more likely to perform these abnormal behaviours than others and there is a suggestion that certain horses may inherit a sensitivity to stress as well as the ability to express the different stereotypic responses when placed in confined or restricted environments. Being able to recognise these horses early in life will ensure that they are housed and managed in such a way so that they do not develop behaviours considered to be undesirable by most horse owners.
In conclusion, it seems most likely that there are core ‘personality’ traits that might be constant within each horse that can be used to predict the way a horse will respond to novel stimuli, different management and training regimes, and overall its suitability for a given role. However more research concerning the objective assessment of individual variation in the behavioural responses of horses to different situations is still required. Only then will it be possible to develop a reliable set of equine temperament tests indicative of relevant and important criteria that can be used for practical purposes and to ensure the best welfare for the horse.