Abstract: For centuries, a goal of training in many equestrian disciplines has been to straighten the horse, which is considered a key element in achieving its responsiveness and suppleness. However, laterality is a naturally occurring phenomenon in horses and encompasses body asymmetry, motor laterality and sensory laterality. Furthermore, forcibly counterbalancing motor laterality has been considered a cause of psychological imbalance in humans. Perhaps asymmetry and laterality should rather be accepted, with a focus on training psychological and physical balance, coordination and equal strength on both sides instead of enforcing “straightness”. To explore this, we conducted a review of the literature on the function and causes of motor and sensory laterality in horses, especially in horses when trained on the ground or under a rider. The literature reveals that body asymmetry is innate but does not prevent the horse from performing at a high level under a rider. Motor laterality is equally distributed in feral horses, while in domestic horses, age, breed, training and carrying a rider may cause left leg preferences. Most horses initially observe novel persons and potentially threatening objects or situations with their left sensory organs. Pronounced preferences for the use of left sensory organs or limbs indicate that the horse is experiencing increased emotionality or stress, and long-term insufficiencies in welfare, housing or training may result in left shifts in motor and sensory laterality and pessimistic mentalities. Therefore, increasing laterality can be regarded as an indicator for insufficiencies in housing, handling and training. We propose that laterality be recognized as a welfare indicator and that straightening the horse should be achieved by conducting training focused on balance, coordination and equal strength on both sides.

Abstract: The aim of this study was to conduct a series of paper-based exercises in order to assess the negative (adverse) welfare impacts, if any, of common interventions on domestic horses across a broad range of different contexts of equine care and training. An international panel (with professional expertise in psychology, equitation science, veterinary science, education, welfare, equestrian coaching, advocacy, and community engagement; n = 16) met over a four-day period to define and assess these interventions, using an adaptation of the domain-based assessment model. The interventions were considered within 14 contexts: C1 Weaning; C2 Diet; C3 Housing; C4 Foundation training; C5 Ill-health and veterinary interventions (chiefly medical); C6 Ill-health and veterinary interventions (chiefly surgical); C7 Elective procedures; C8 Care procedures; C9 Restraint for management procedures; C10 Road transport; C11 Activity—competition; C12 Activity—work; C13 Activity—breeding females; and C14 Activity—breeding males. Scores on a 1–10 scale for Domain 5 (the mental domain) gathered during the workshop were compared with overall impact scores on a 1–10 scale assigned by the same panellists individually before the workshop. The most severe (median and interquartile range, IQR) impacts within each context were identified during the workshop as: C1 abrupt, individual weaning (10 IQR 1); C2 feeding 100% low-energy concentrate (8 IQR 2.5); C3 indoor tie stalls with no social contact (9 IQR 1.5); C4 both (i) dropping horse with ropes (9 IQR 0.5) and forced flexion (9 IQR 0.5); C5 long-term curative medical treatments (8 IQR 3); C6 major deep intracavity surgery (8.5 IQR 1); C7 castration without veterinary supervision (10 IQR 1); C8 both (i) tongue ties (8 IQR 2.5) and (ii) restrictive nosebands (8 IQR 2.5); C9 ear twitch (8 IQR 1); C10 both (i) individual transport (7.00 IQR 1.5) and group transport with unfamiliar companions (7 IQR 1.5); C11 both (i) jumps racing (8 IQR 2.5) and Western performance (8 IQR 1.5); C12 carriage and haulage work (6 IQR 1.5); C13 wet nurse during transition between foals (7.5 IQR 3.75); and C14 teaser horse (7 IQR 8). Associations between pre-workshop and workshop scores were high, but some rankings changed after workshop participation, particularly relating to breeding practices. Domain 1 had the weakest association with Domain 5. The current article discusses the use of the domain-based model in equine welfare assessment, and offers a series of assumptions within each context that future users of the same approach may make when assessing animal welfare under the categories reported here. It also discusses some limitations in the framework that was used to apply the model.

Abstract: Bringing the head and neck of ridden horses into a position of hyperflexion is widely used in equestrian sports. In our study, the hypothesis was tested that hyperflexion is an acute stressor for horses. Salivary cortisol concentrations, heart rate, heart rate variability (HRV) and superficial body temperature were determined in horses (n = 16) lunged on two subsequent days. The head and neck of the horse was fixed with side reins in a position allowing forward extension on day A and fixed in hyperflexion on day B. The order of treatments alternated between horses. In response to lunging, cortisol concentration increased (day A from 0.73 ± 0.06 to 1.41 ± 0.13 ng/ml, p < 0.001; day B from 0.68 ± 0.07 to 1.38 ± 0.13 ng/ml, p < 0.001) but did not differ between days A and B. Beat-to-beat (RR) interval decreased in response to lunging on both days. HRV variables standard deviation of RR interval (SDRR) and RMSSD (root mean square of successive RR differences) decreased (p < 0.001) but did not differ between days. In the cranial region of the neck, the difference between maximum and minimum temperature was increased in hyperflexion (p < 0.01). In conclusion, physiological parameters do not indicate an acute stress response to hyperflexion of the head alone in horses lunged at moderate speed and not touched with the whip. However, if hyperflexion is combined with active intervention of a rider, a stressful experience for the horse cannot be excluded.

Abstract: The heart rates (HR) of horses and the people leading them (10 horses, 20 people), and riding them (17 horses, 17 people), were recorded in an indoor arena. The horses were Swedish leisure horses of mixed ages, sex and breed. All except two of the people were female and all were of mixed age and riding experience. Each horse–human pair walked or rode between points A and B (30 m) four times on each test occasion. However, just before the fourth pass, participants were told that an umbrella would be opened as they rode, or led, the horse past the assistant. The umbrella was not opened, so this pass was no different to the previous control occasions, but nevertheless there was an increase in HR for both the person (leading, P = 0.06; riding, P < 0.05) and the horse (being led, P < 0.05; being ridden, P < 0.05). The findings indicate that analysis of HR recorded simultaneously from people and horses under different experimental handling or riding conditions presents a useful tool to investigate horse–human interactions.

Abstract: The long-held belief that human dominance and equine submission are key to successful training and that the horse must be taught to [`]respect' the trainer infers that force is often used during training. Many horses respond by trialling unwelcome evasions, resistances and flight responses, which readily become established. When unable to cope with problem behaviours, some handlers in the past might have been encouraged to use harsh methods or devices while others may have called in a so-called [`]good horseman' or [`]horse whisperer' to remediate the horse. Frequently, the approaches such practitioners offer could not be applied by the horse's owner or trainer because of their lack of understanding or inability to apply the techniques. Often it seemed that these [`]horse-people' had magical ways with horses (e.g., they only had to whisper to them) that achieved impressive results although they had little motivation to divulge their techniques. As we begin to appreciate how to communicate with horses sensitively and consistently, misunderstandings and misinterpretations by horse and trainer should become less common. Recent studies have begun to reveal what comprises the simplest, most humane and most effective mechanisms in horse training and these advances are being matched by greater sharing of knowledge among practitioners. Indeed, various practitioners of what is referred to here as [`]natural horsemanship' now use techniques similar to the [`]whisperers' of old, but they are more open about their methods. Reputable horse trainers using natural horsemanship approaches are talented observers of horse behaviour and respond consistently and swiftly to the horse's subtle cues during training. For example, in the roundpen these trainers apply an aversive stimulus to prompt a flight response and then, when the horse slows down, moves toward them, or offers space-reducing affiliative signals, the trainer immediately modifies his/her agonistic signals, thus negatively reinforcing the desired response. Learning theory and equine ethology, the fundamentals of the emerging discipline of equitation science, can be used to explain almost all the behaviour modification that goes on in these contexts and in conventional horsemanship. By measuring and evaluating what works and what does not, equitation science has the potential to have a unifying effect on traditional practices and developing branches of equitation.