international equitation science symposium 2005

The 1st International Equitation Science Symposium was held at the The Australian Equine Behaviour Centre on the 26th and 27th August, 2005. 90 Delegates from 7 countries attended, showing the burgeoning interest in a more objective and scientific understanding of the processes of horse training. The following peer-reviewed papers were presented:   

1. The evolution of schooling principles and their influence on the horse's welfare. Ödberg FO
2. Defining the terms and processes associated with equitation. McGreevy PD, McLean AN, Warren-Smith AK, Waran N and Goodwin D
3. A low cost device for measuring the pressures exerted on domestic horses by riders and handlers. Warren-Smith AK, Curtis RA and McGreevy PD
4. Breed differences in equine retinae.   Evans KE and McGreevy PD
5. Equestrianism and horse welfare: The need for an ‘equine-centred' approach to training. Waran N
6. The use of head lowering in horses as a method of inducing calmness. Warren-Smith AK and McGreevy PD
7. Epidemiology of horses leaving the Thoroughbred and Standardbred racing industries. Hayek AR, Jones B, Evans DL, Thomson PC and McGreevy PD
8. A preliminary study on the relation between subjectively assessing dressage performances and objective welfare parameters. de Cartier d'Yves A and Ödberg FO

Defining the terms and processes associated with equitation

McGreevy PD1, McLean AN2, Warren-Smith AK3, Waran N4 and Goodwin D5

1 Faculty of Veterinary Science (B19), University of Sydney, NSW 2006, Australia.
2Australian Equine Behaviour Centre, Clonbinane Road, Broadford, VIC 3658, Australia.
3 Faculty of Rural Management, Charles Sturt University, PO Box 883, Orange, NSW 2800,
Australia.
4Animal Welfare Group, Unitec New Zealand, Private Bag 92025, Auckland, New Zealand.
5School of Psychology, University of Southampton, Southampton, SO17 1BJ, UK.

The need for precise definitions is accepted in human psychiatry (DSM-IV, 1994) and is increasingly called for in veterinary behaviour medicine (Overall, 1997; 2005). In contrast, the use of non-scientific terms is customary in equestrian circles and is added to by contemporary trainers and self-styled horse whisperers. Data suggest that qualified equestrian instructors frequently confuse the meaning of terms that originated in behavioural science (Warren- Smith and McGreevy, in prep). Several descriptors may be used for the same behaviour, depending on the observer (Mills, 1998). The use of such terms may encourage imprecise and inappropriate interpretations of equine behaviour. For example, many layman’s terms imply subjective mental states in the horse and that horses are culpable participants in the training process. These assumptions can have negative welfare implications for the domestic horse and safety implications for riders and handlers (McLean, 2004).

Publication of the Equid Ethogram (McDonnell, 2003) is welcomed, since it defines terms that appear in the literature on free-ranging and managed horses. However, the Equid Ethogram includes discussion on few human-horse interactions. Since equitation science seeks to improve the welfare of horses and improve clarity of communication in their interface with humans, it is appropriate to address this apparent gap in the agreed hippological terminology. This paper advocates the need for a glossary of terms that provide a scientific framework on which to base future discussions and debate. The challenge for equitation science is to define and quantify as many elements of the interaction between riders and horses as possible. Ethological and anatomical nomenclature can and should be used to describe a horse’s manoeuvres but the description and measurement of more conceptual and less tangible qualities, such as feelings (including happiness), depends on the development of more innovative techniques than are currently available. That said, it is possible to quantify acute and chronic stress through the measurement of heart rate and corticosteroid concentrations.

The glossary and definitions offered below will be presented at the First International Equitation Science Symposium and remain a living document that can be reviewed by subsequent symposia and downloaded from a nominated web-site. Underlined words have separate entries in this glossary.

Above the bit: A posture characteristic of a hyper-reactive ridden horse exhibiting conflict behaviour in which the horse attempts to escape the aversive situation by raising its head, quickening the pace, shortening its neck and stride and bracing its back, which becomes dorsally concave. The horse thus assumes a posture appropriate for running and therefore does not show impulsion.

Accepting the bit: The way a horse responds to the bit in particular and aids in general. During locomotion and transitions, the horse’s mouth remains closed, soft in the jaw and with relaxed lips. A horse that accepts the bit does not shorten or lengthen its neck or alter its head position during travelling and transitions. Accepting the bit is generally accompanied by relaxation of the neck and body.

Activity: The rhythmical speed of movement of the horse’s legs within any gait. See Tempo.

Against the hand: When a horse does not stop/slow/step-back from the bit correctly. Consequently the rein contact feels heavy to the rider. This is usually accompanied by a hyper-reactive (hollow) posture in which the neck shortens or lengthens during locomotion or transitions. There may be an element of learned helplessness in this behaviour. A horse may also be described as being against one of the rider’s hands, in which case it is heavy on one rein only (lugging), demonstrating a diminished response to the turn signal of that rein.

Against the leg: A description of a horse that is not straight in its body and is continually flexing its thorax (see Flexion) against one of the rider’s legs. Such a horse drifts or attempts to drift sideways. In addition, the horse may be against both legs (i.e., not going forward).

Aid: Any of the signals or cues used to elicit responses in horses. Rein, leg, whip and spur aids are initially learned through negative reinforcement and then transformed to light aids (light rein, light leg, voice, seat) via classical conditioning because of the temporal relation between the two. In traditional horsemanship, the aids are divided into two groups: the natural aids and the artificial aids. This distinction is misleading as it neither identifies nor correlates with the two different learning modalities through which the horse acquires its responses to the aids.

Artificial aids: Equipment used to alter a horse’s behaviour under-saddle or inhand (e.g., whips, spurs). When employed correctly, these are generally used to negatively reinforce various locomotory responses and are most commonly used to fortify the light or natural aid to achieve the desired response. By convention, these are distinct from the natural aids since they do not involve direct use of parts of the rider’s body.

Asking with the rein: Cues sent by the rider through the rein to signal the horse
to respond in a specific way.

Balanced seat: The position of a mounted rider that requires the minimum of muscular effort to remain in the saddle and which interferes least with the horse’s movements and equilibrium. It is generally understood that the balanced seat allows delivery of the aids in the most effective manner. The rider has equal weight on both seat bones and feet. See Independent seat.

Bars of the mouth (diastema): Area of the horse’s mandible between the incisors and the molars that is free of teeth and in which the bit lies.

Baulk: Refuse to move forward, usually because of the presence of an aversive object or obstacle (as in jumping). See Napping.

Behind the bit: A head and neck posture that is generally described as an evasion and which involves the horse persistently drawing its nose toward its chest, sometimes allowing the reins to become slack. This occurs in training because of mistakes made in negative reinforcement or due to the use of restraining devices (such as draw reins) that force the neck to be shortened. In this situation the horse gives two different and independent responses to one signal (i.e., slowing or dorsoventral flexion) and thus frequently develops conflict behaviour. This posture thwarts the development of impulsion.

Behind the leg: A horse that lacks self-maintained speed and rhythm requires the rider to continually deliver leg aids with each stride or each alternate stride.

Behind the vertical: The appearance of a horse with a shortened neck posture. As a result, it positions its nasal planum behind the vertical line (the horse’s chin becomes closer to its chest). Such a horse is generally heavy in the feel of the reins or has no contact during locomotion and transitions and, when this occurs, its stop/slow/step-back response is diminished. As the horse offers two independent responses (shortening neck or slowing) to one signal, it often exhibits conflict behaviours.

Bend (lateral bend): The lateral curvature of the body that arises principally by the flexing of four sites of the horse’s vertebral column: the cervical region in general, and the thoracic (10th thoracic vertebra), lumbar (1st lumbar vertebra) and sacral (3rd sacral vertebra) regions (Faber et al., 2001). Bend allows the horse to step into its fore tracks with its hind feet on a curved line or circle that is greater than 6 m in diameter. Bend is usually accompanied by flexion, lateral, longitudinal and vertical, and is an accepted correct feature of all work on curved lines and all lateral movements.

Bit: An apparatus usually consisting of metal or other hard substances or a combination of both. It is positioned in the diastema of the horse’s mouth and connected to the reins. As a result of tension in the reins, this apparatus places pressure on the lips, tongue and bars of the horse’s mouth and results in the horse learning to stop/slow/step-back and turn, through the processes of negative reinforcement and classical conditioning.

Bitting: Accustoming a horse to having a bit in its mouth or the selection of the most appropriate bit for a horse.

Blocking: a) Preventing a horse from performing appropriately in any given gait by the application of simultaneous rein and leg pressure. This can result in conflict behaviour.
b) The deleterious effects of the simultaneous application of two intense aids such that neither will be learned (Hull, 1943).

Blow-up: When a ridden or handled horse becomes hyper-reactive during training and exhibits behaviours ranging from mild tension to bucking or breaks from the gait in which it is meant to be travelling. It is most common in early training and exposure to novel environments as in ‘showing’. It is generally a symptom of conflict behaviour.

Bolting: a) Accelerating, usually to a gallop out of stimulus control (see Running away) and showing a lack of response to the stop/slow/step-back cues. Bolting reflects an extreme activation of the HPA axis (hypothalamic-pituitaryadrenal axis). This is a manifestation of conflict behaviour. Sometimes referred to as ‘running blind’.
b) Eating (concentrated food) too rapidly.

Break gait: The random change from one gait to another that is not under stimulus control.

Break in (gentle, start): The basic foundation training of a young horse to respond to aids and cues that control its rhythm and tempo, direction and posture for whatever purpose it may be required.

Bridle lameness: An irregularity of gait under-saddle that has the appearance of lameness. Mostly seen in the trot, it arises as a result of a long-term training error in which the horse is unable to free itself of simultaneous and persistent bit and leg pressure during locomotion and transitions, or from persistent rising on the same or incorrect diagonal at trot. There is usually an associated crookedness to the longitudinal axis of the body.

Broken neck (over-bent): The appearance of the neck of a horse in which there is a (usually) sudden change in angle (a break in the curve) in the vicinity of the third cervical vertebra. This is usually a result of persistent use of side reins that are too short, especially during early training, or draw reins that cause the neck to be too flexed and the nasal planum to be behind the vertical. It is believed that there is degeneration of the vertebrae and/or ligaments at the third cervical vertebra. Horses with broken necks generally exhibit conflict behaviours and tend to flex their necks to light rein pressure rather than give the stop/slow/step-back response.

Bronco: An unbroken or imperfectly broken wild horse, or one maintained in this state for rodeos.

Bucking: A sudden humping or arching of the back with the head and neck lowered, usually kicking out with the hindlegs or jumping/bounding forwards/sideways with an arched back and ears laid back (Waring, 2003). Bucking is a manoeuvre that evolved to dislodge predators. Persistent bucking is a manifestation of conflict behaviour to the rein and leg aids (McLean, 2005).

Cadence: The result of the combined effect of correct training that a horse shows when it moves with well-marked regularity, impulsion, balanced and rhythmic strides. There should be an enhanced period of suspension between steps that gives the horse the appearance of springing off the ground so the feet lift clear of the ground and float to the next step.

Champing (US): See Mouthing.

Cinch bound (US): See Cold-back.

Classical conditioning: The process whereby the unconditioned or conditioned response becomes elicited from a conditioned stimulus (Pavlov, 1927). In equitation it is the process where learned responses are elicited from more subtle versions of the same signal or to entirely new signals.

Cold-back (girth shy, US Cinch bound): Hyper-reactive behaviour (occasionally bucking) or instability sometimes to the extent of collapse when the girth is tightened, the saddle is placed on the back or a horse is mounted.

Cold-jawed (US tough-mouthed): See Hard-mouthed.

Collected walk/trot/canter: Where each step of the stride of the gait is shorter and higher rather than longer. The horse should remain on the bit, the hindquarters should be engaged (lowered), with the horse showing activity, impulsion and lightness. Collected paces should develop from the correct schooling of the horse over time so that it is physically able to travel showing true collection.

Collection: The progressive development of increased carrying power in the hindquarters of the horse. The resultant transfer of weight from the forequarters to the hindquarters allows the poll and withers to be carried higher, the hindquarters to drop slightly and the hind feet to step further forward and to carry more bodyweight with higher and shorter steps. This confers more power to the hindquarters, enabling the horse to perform more collected movements. In classical equitation, collection develops from repeated gait and stride length transitions that occur in three beats of the rhythm. The combined effect of the transitions and the inertia of the animal result over time in changes in the horse’s physique. The propulsion of the body is then in a more upward and forward direction giving greater cadence to the strides and increased lightness of the forehand (Anon, 1986). See also False collection.

Conflict behaviour: A set of responses of varying duration that are usually characterised by hyper-reactivity and arise largely through confusion. In equitation, confusions that result in conflict behaviours may be caused by application of simultaneous opposing signals (such as go and stop/slow/stepback) such that the horse is unable to offer any learned responses sufficiently and is forced to endure discomfort from relentless rein and leg pressures. Attempts to flee the aversive situation result in hyper-reactivity. In addition, the desired response to one or both aids diminishes. Conflict behaviours may also result from one signal eliciting two or more responses independently, such as using the reins to achieve vertical flexion independently of the stop/slow/step-back response, or using a single rein to bend the neck of the horse independently of its previously conditioned turn response. Similarly, conflict behaviour may result from incorrect negative reinforcement, such as the reinforcement of inconsistent responses, incorrect responses, no removal of pressure or no shaping of responses. Often referred to as evasions and resistances.

Conformation: Features of the external morphology (i.e., the relative musculoskeletal dimensions) of a horse that interest breeders and exhibitors, not least because they can affect its performance (Loch, 1977).

Connection: The contact of the rein, seat and leg. This contact may be absent (no connection), correct (an easily habituated light connection) or too strong (unendurable pressure).

Contact: The connection of the rider’s hands to the horse’s mouth, of the legs to the horse’s sides and of the seat to the horse’s back via the saddle. The topic of contact with both hand and leg generates considerable confusion related to the pressure that the horse should endure if the contact is deemed to be correct. In classical equitation, contact to the rein and rider’s leg involves a light pressure (approximately 200 g) to the horse’s lips/tongue and body, respectively. Although a light contact is the aim, there are brief moments, (seconds or parts of a second), when contact may need to be stronger, particularly at the start of training, or in re-training, to overcome resistances from the horse. Many contemporary horse trainers insist that the contact should be much heavier than a light connection. This view may cause progressive habituation leading to learned helplessness to the rein and leg signals as a result of incorrect negative reinforcement and/or simultaneous application of the aids. Contact may therefore need to be the focus of discussion and debate.

Counter-bending, counter-flexing: The practice of bending or flexing the horse to the outside of the circle or away from the direction of turn. As flexion and bend are shaped qualities of the turn response, counter-bending and counter-flexing can result in conflict behaviour because no turn response is involved.

Crabbing: A conflict behaviour in ridden and in-hand horses where the horse fails to go straight and the resistance manifests as a sideways and forward (frequently alternating the direction) crab-like motor behaviour. Crabbing may also be associated with a hyper-reactive horse under restraint.

Cue: An event that elicits a learned response. In equitation, cues are termed aids. These are learned through classical conditioning when a response comes increasingly under stimulus control.

Deep and round (rolkür): A modern tendency to train the horse to carry its head low and its cervical vertebrae maximally flexed (chin closer to the chest) in the belief that the hindquarters are engaged and that the activity and power of the hindlegs is improved. To critics, the deep and round technique is seen as a form of false collection and may have welfare implications.

Detraining: Where a stimulus is applied without the learned response being performed. The result is reduction or extinction of the likelihood of the learned response arising from the stimulus.

Diagonal: a) Refers to the forefoot moving in unison with the opposite hind foot as seen in the gaits of trot (two diagonal pairs) and canter (one diagonal pair).
b) Being on the correct diagonal refers to the rising and sitting of the rider being synchronised with the trotting horse’s footfalls so that the rider sits when the outside foreleg and inside hindleg are on the ground and rises as they move forward.

Diagonal advanced placement (DAP): As a result of incorrect negative reinforcement and in particular the simultaneous application of forward and restraining pressures accompanied with maximal flexion of the cervical vertebrae (rolkür), it has been suggested that the diagonal pairing of legs during the trot and canter may be temporally split, with subsequent losses in the purity of the gaits and the possible emergence of conflict behaviours (See Rolkür).

Direct rein/indirect rein: A direct rein is one held out wide away from the neck in an attempt to make the turn response clearer to the horse. By contrast, an indirect rein is one that is parallel to the horse’s neck. For the horse to turn in response to an indirect rein, it must already have a clear learned response.

Disunited canter: An undesirable broken gait, most often seen in horses with a tendency to pace or horses that are not straight (see Straightness). It occurs when there is a shift from ipsilateral to contralateral coupling of fore and hindlegs.

Dominance/submission: Suites of behaviours in social interactions that signal rank or determine priority of access to resources (a dynamic process affected by motivation). A belief in horse training that horse interactions are governed by dominance/submission implies that trainers need to be dominant over horses to train them effectively. This notion that a horse must respect a human to be effectively controlled may be at odds with learning theory. In equitation the significance of dominance, submission and respect need further investigation.

Double-gaited: A horse that can both trot and pace.

Downhill: Conformational fault in a dressage horse, where the horse is noticeably higher at the point of the croup than at the withers. Such a horse may feel heavy on the forehand to the rider.

Driving: a) Where either a horse or a team of horses pulls a vehicle.
b) See Long-reining.
c) Locomotion (see Engagement) in which the horse is pushing forward with its hocks underneath it at the moment of pushing. The moment of push should not continue to where the fetlock is behind the vertical line of the hock.

Engagement/engaging the hocks (tarsal joints): Where the horse brings its hind feet underneath its body so that proportionally more weight is placed on the hindlegs. Classically, this process is trained over time with concomitant physique changes; however, in contemporary training, it is sometimes produced by riders forcing the horse to shorten and raise its head and neck with rein pressure while simultaneously applying leg/forward pressure. Deep and round is frequently used as a precursor to this technique termed false collection. It should be clear that engagement is not the same as collection, but is a precursor to it.

Evading the bit: Oral behaviours (such as moving the tongue aborally) and neck postures (such as dorsoventral flexion) that enable horses to reduce the discomfort caused by bits or the extent to which riders can apply and maintain pressure. In training, these result from errors in negative reinforcement.

Evasions and resistances: Descriptive terms for conflict behaviours where evasions are similar to resistances, except that evasions refer to the more severe and violent behaviours. These terms arose because of the horse’s natural tendency to avoid pressure/pain by learning through negative reinforcement to perform any attempted behaviour that results in lessening of pressure/pain. The problem with these terms is that they imply malevolent and calculated behaviour on the part of the horse whereas, in fact, these behaviours are more likely the result of errors in negative reinforcement.

Extension/extended strides: The longest stride within the rhythm of the particular gait. In equitation, extended paces arise only from collected paces. These strides involve straightened limbs at the end of the swing phase of the stride that allow the horse to cover as much ground as possible with each stride. For the average horse, in the extended walk and trot, the hind track should land approximately 20 to 30 cm in front of the fore tracks and in extended canter the hind tracks land about 2 m in front of the fore tracks.

False collection: Forcing a horse into an apparently collected outline through the simultaneous actions of the rein and leg or with the use of gadgets and pulleys rather than the progressive development of collection over time through training. False collection frequently results in conflict behaviour because concurrent stop and go signals cause confusion and pain.

Flexion: a) Longitudinal: The dorsoventral lowering, lengthening and relaxing of the horse’s neck and back. In reality this is not a flexion but an extension and should be redefined as longitudinal extension. This is the most fundamental quality of being on the bit. Longitudinal flexion should not be confused with ‘longitudinal bend’ (See Impulsion).
b) Lateral: The lateral bending of the atlanto-occipital junction and including the first three cervical vertebrae of the horse’s neck. This is primarily a shaped quality of correct turning and in the well-trained horse is thus involved whenever the turn, circles or the turn-position is required such as in lateral movements. The extent of lateral flexion negatively correlates with the size of the circle. As lateral flexion is a shaped quality of the turn response, counter-flexing can result in conflict behaviour. Lateral flexion is a secondary precursor of being on the bit. Lateral flexion should not be confused with ‘lateral bend’ (See Bend).
c) Dorsoventral, vertical or direct: The dorsoventral flexion of the horse’s cervical vertebrae so that the nasal plane is almost perpendicular to the ground (the nasal plane may be up to 6 degrees in front of vertical). For a horse to be showing vertical flexion it must be relaxed, straight, pushing forward from behind with its hocks underneath it, relaxed in its jaw and showing longitudinal flexion (Wallace, 1993). This is a precursor of the horse being on the bit. Dorsoventral flexion may be seen as a result of correct longitudinal flexion.

Falling in/ falling out: Losses of straightness associated with the horse drifting in or out of the circle. Similar to lugging, but more apparent at the slower gaits.

Forehand (forequarters): Those parts of the horse that lie in front of the rider (i.e., the head, neck, shoulders, withers and forelegs).

Freeze: The sudden alert motionless stance associated with a highly attentive reaction to an external stimulus (often visual) and typically resulting in conflict behaviours such as napping/spinning.

Girth shy: See Cold-back.

Go: The acceleration response in horse training that provides forward motion. The go response is trained via negative reinforcement using the rider’s legs under-saddle and using anterior lead rein pressure when working a horse inhand. Through classical conditioning, these responses are converted first to light versions of the leg or lead rein and then to the cues of seat, position and perhaps voice.

Good mouth: See Soft mouth.

Green: a) An inexperienced horse with no training or one that has undergone foundation training but is not fully trained.
b) A racehorse that has yet to undergo a time trial.

Habituation: The waning of a response to a repeated stimulus as a result of frequent exposure (not fatigue).

Half-halt: A subtle, sequential application of the seat, leg and rein aid that is separated in time by one beat of the rhythm of the gait. The half-halt is intended to increase the attention and balance of the ridden horse.

Hanging: See Lugging.

Hard-mouthed (US Cold-jawed, tough-mouthed): Habituation to rein pressure. This is generally a result of incorrect negative reinforcement and can result in learned helplessness and conflict behaviours in susceptible animals.

Hitch: a) To tether a horse.
b) A defect in gait noted in the hindlegs, which seem to skip at the trot.

Hollow: Undesirable contraction of the vertebral column, so that the head comes up and the neck and back become slightly concave. The strides of the horse generally become faster and shorter (‘choppy’). Habitual hollowness is usually a result of incorrect negative reinforcement and is frequently associated with conflict behaviours. Because of its reported association with activation of the HPA axis, hollowness should be further researched.

Horse breaking: See Break in

HPA axis (Hypothalamic–Pituitary–Adrenal axis): The physiological response to arousal, involving the limbic system, which stimulates the hypothalamus to produce corticotrophin releasing factor, which in turn stimulates the anterior pituitary gland to produce adrenocorticotrophic hormone, which then stimulates the adrenal cortex to secrete glucocorticoids.

Hyper-reactive behaviour: Behaviours characteristic of an activated HPA axis and associated with various levels of arousal. Such behaviours typically involve the horse having a hollow posture and leg movements with increased activity and tempo, yet shorter strides. Hyper-reactive behaviours are quickly learned and resistant to extinction because of their adaptiveness in the equid ethogram. Behavioural evidence of hyper-reactivity ranges from postural tonus to responses such as shying, bolting, bucking and rearing.

Impulsion: The response of a horse that is correctly trained in its go/stop responses so that it moves forward energetically with a self-maintained rhythm, straightness and outline when signalled to do so. Impulsion is an early expression of the progressive development of collection, in which the animal progressively carries more weight on its hindquarters. There have been proposed to be three types of impulsion: 1. Instinctive - i.e., the inherited tendency to have more or less impulsion; 2. Mechanical - develops from Instinctive Impulsion and improves with work and gymnastic training; 3. Transmitted - that given to the horse by the rider in collecting the horse (Winnett, 1993). True impulsion, in which the horse conveys itself calmly under a light rein and without constant pressure from the rider, is distinct from states of general excitement in which the horse pulls at the bit and requires forceful restraint to be controlled.

In front of the leg: A desirable quality in equitation describing a horse with a correctly trained go response such that it is neither slowing nor accelerating of its own volition (i.e., it self-maintains its rhythm).

Independent seat: The ability of a rider to maintain a secure, firm and balanced position on a horse’s back, without relying on the reins or stirrups. See Balanced seat.

In-hand: In a routine of schooling in-hand, the trainer works from the ground rather than from the saddle, positioned beside and/or behind the horse and controlling it with rein, voice and schooling whip. In-hand work allows the horse to acquire signal response entities of go and stop as a prelude to foundation training, or during retraining or when training advanced movements.

Inside/outside: Identifies either side of the horse as it is being schooled. These require some clarification as to whether one is referring to the relative position in the arena, to the curvature of the path, or to the bend of the horse (e.g., inside leg usually refers to the leg of the rider or horse nearest to the centre of the circle the horse is following, or on the bent side, which can be the outside of the arena as in renvers).

Jog: a) A slow, short-striding trot, usually associated with heightened arousal and involving short choppy steps and constant tendencies to accelerate as the horse is attempting to flee the aversive situation. Habitual jogging can be associated with conflict behaviours and result in diminished responses to the slow/stop/step-back signals (McLean, 2005).
b) In harness racing the term given to the exercise conducted on non-hopple days. (Hobble = restraint, hopple = harness).
c) A slow trot used mainly in Western pursuits.

Join-up: An element of round-pen training (popularised by US trainer Monty Roberts) in which the horse learns to remain close to the human.

Lateral movements: Any of the schooling exercises (such as leg-yield, shoulder-in, travers, renvers and half-pass) that involve the horse having longitudinal bend and travelling with the forelegs and hindlegs on two, three or four different tracks with the aim of improving its engagement and collection.

Leadership: A belief in natural horsemanship that requires debate owing to its inherent anthropomorphism. According to this theory, the horse must accept the human as a leader to respond correctly in training. This assumption may be contradicted by learning theory, so the significance of leadership in equitation calls for further study.

Leaning on the bit: A sign of habituation to bit pressure which manifests with the horse persistently pressuring the rein(s) as though relying on the rider to support the weight of its head. This arises through incorrect negative reinforcement and can be associated with conflict behaviours and learned helplessness.

Learned helplessness: A state in which an animal has learned not to respond to pressure or pain. Arises from inappropriate application of negative reinforcement, which results in the horse not being able to obtain release from aversive stimuli. If this continues over a period of time the horse will no longer make responses that were once appropriate. Learned helplessness has the following characteristics: a disinclination to trial behavioural responses to pressure; lowered levels of aggression; dullness; loss of appetite; physiological and immunological changes.

Leg-yield: The simplest of lateral movements in which the horse moves both forward and sideways from the rider’s single leg signal. Leg-yield is usually trained before more complex lateral manoeuvres. In leg-yield, the horse is almost straight, except for slight lateral flexion away from the direction of travel.

Lightness: A desirable quality that reflects self-carriage and the horse’s self-maintenance of rhythm, straightness and outline. Lightness involves the bringing into action by the rider and the use by the horse of only those muscles necessary for the intended movement. Activity in any other muscle groups can create resistance and thus detract from the lightness.

Long-reining: A method of schooling the horse using two reins, each attached to the horse’s bit and returning to the handler, who moves behind and/or beside the horse, as if driving it without being attached to any vehicle or load. Long-reining is sometimes used as a prelude to foundation training, retraining or in the training of advanced movements.

Long and low: Training the horse to go with its poll extended and lowered and its neck slightly dorsoventrally flexed while attempting to achieve more activity and impulsion.

Loose schooling: Often used as an alternative to lunging, long reining or round pen for exercise and training. The horse is typically loose schooled in the outer lane of an arena and frequently encounters grid exercises or series of fences for jumping on pre-determined distances and stride patterns and so is said to learn independently.

Lope: The Western version of a very slow canter, this is a smooth, slow gait in which the head is carried low.

Lugging: A term, mostly used in horse-racing, that refers to a straightness problem where the horse drifts sideways, particularly at the gallop. In doing so, the horse becomes heavy on the rein on the side away from which it is drifting. A horse that habitually lugs does so as a result of incorrect negative reinforcement, because the rider holds the heavy rein tighter as he attempts to maintain a straight line; in other words, there is a bilateral difference in turn cues.

Lunge (also longe): Exercising a horse in circles with the trainer in the middle of the circle using a long lead/rein or rope. Lunging is used to habituate a horse to the saddle during foundation training, to train obedience, to warm up a horse and to tire a hyper-reactive horse.

Mouthing: a) The process of habituating a horse to a bit in its mouth and learning to respond to the stop/slow/step-back and turn signals of the reins.
b) Champing (US): Where the horse gently moves the bit. Mouthing is a response that is sometimes encouraged in bitting a young horse. Use of a bit with ‘keys’ attached to the mouthpiece facilitates saliva flow and keeps the mouth moist.

Napping, propping: When a horse fails to respond appropriately to the rider’s signals, as in refusing to go forward, running sideways, spinning or running backwards. This conflict behaviour could also result in attempts at rearing.

Natural aids: The body, seat, hands (reins), legs, weight and voice, as used to signal to the horse. Some of these aids are acquired via negative reinforcement (e.g., leg and rein responses), while others are acquired by classical conditioning (e.g., weight and voice aids). The distinction therefore is not based on learning theory.

Natural horsemanship: A relatively modern system of horse training that originated in Western training. It is based on an interpretation of the natural ethogram of the horse. Natural horsemanship focuses on concepts of dominance/submission, respect and leadership, which are currently controversial and may be at odds with learning theory.

Neck rein: To turn or steer a horse by pressure of the rein on the neck.

Negative reinforcement: The subtraction of something aversive (such as pressure) to reward the desired response and thus lower the motivational drive (Skinner, 1953).

Obedience: In traditional horsemanship, compliance to the aids. Perhaps a more objective definition is the horse’s immediate initiation of the required response to a light aid (McLean, 2003).

Off the bit: A lack of at least one of the three prerequisites for on the bit; usually referred to as being above the bit or behind the bit. The horse does not have a contact or connection to the rider’s hands through the reins.

On the bit: The self-maintained neck and head position of the horse in correct schooling where vertical flexion of the cervical vertebrae and atlanto-occipital joint (also known as poll flexion or roundness) results in the nasal planum being approximately 6 degrees in front of the vertical or 12 degrees at walk. This posture is intended to improve the balance of the ridden horse (relocating extra weight to the hindquarters) and its willingness to respond to the signals transmitted by the rider through the reins. There are three precursors to the horse being on the bit. The first is longitudinal flexion, followed by lateral flexion and finally vertical flexion. To most people, ‘on the bit’ means that the horse travels with its neck arched and nose tucked in. However, a vertical nose does not necessarily mean that the horse is on the bit. On the bit is necessary in horse training because, as a result of vertical flexion, the centre of gravity shifts posteriorly toward the rider’s centre of gravity. There are various forms of false roundness where the horse is forced by the rider’s hands or with the use of mechanical devices to flex his cervical vertebrae.

On the forehand: An undesirable form of locomotion that involves the horse carrying an inappropriate proportion of its weight on its forequarter, a posture that runs counter to impulsion, collection and self-carriage. Usually seen in young or poorly schooled horses where the withers appear lower than the croup of the horse during locomotion.

Operant conditioning: Training the horse to respond consistently to signals through positive reinforcement and negative reinforcement (Skinner 1938; McLean, 2003).

Out behind: See Trailing hindquarters.

Outline (US shape, frame): An aspect of the horse’s posture that refers to the curvature of the vertebral column and so encompasses the degree of flexion of the neck and poll and the associated flexion of the lumbosacral region. According to the ideals of equitation, the nasal planum should be no more than 12 degrees from the vertical at the walk and 6 degrees from the vertical at other gaits and never behind the vertical, because such a departure results in loss of self-carriage and lightness. The back should be soft and relaxed and give the impression of being raised.

Outside: See Inside/outside.

Over-bent (Broken-neck): Where the horse assumes a posture in which its nasal planum is described as being behind the vertical. Usually caused by faults in negative reinforcement, such as unrelenting pressure from the rider’s hands on the bit.

Overface: Undertaking a task during riding or training that is beyond the horse’s capacity or current experience.

Over-shadowing: The effect of two signals of different intensity being applied together, such that only the most intense will result in a learned response (Hull, 1943).

Pace: A two-time lateral gait in which the hindleg and the foreleg on the same side move together.

Pig-rooting: A conflict behaviour involving lowering the head and arching of the back and a kick out or bounding of the back legs (a minor form of bucking) often as a prelude to bucking.

Positive reinforcement: The addition of something pleasant (a reinforcer) to reward the desired response and thus lower the motivational drive for that reinforcer (Skinner, 1953; McLean, 2003).

Progressive desensitisation: A step-by-step weakening of an fear response to a given stimulus or set of stimuli to the point of extinction (McGreevy, 2004).

Pulling: See Lugging.

Punishment: The presentation of an aversive stimulus that decreases the likelihood of response or, in the case of negative punishment, the removal of a reinforcing stimulus. Punishment is often used incorrectly in horse training (i.e., when not contingent with the offending response). Incorrect use of punishment can lower an animal’s motivation to trial new responses, desensitise the animal to the punishing stimulus and create fearful associations (Mills, 1998a).

Purity of the gaits: The regular temporal sequence of the natural footfalls of the gaits of the horse. These are considered fundamental to the sport and practice of dressage (F.E.I., 2003). When these are not present due to incorrect negative reinforcement or the simultaneous application of go and stop/slow/step-back pressures, hyper-reactive behaviours may emerge and conflict behaviours may develop.

Rapping, touch up: Inappropriate strategy used to sensitise the legs in an attempt to improve jumping performance in the horse, various substances being applied to the anterior aspects of the 3rd metacarpal or cannon of the forelimbs such that the horse will avoid hitting a fence when jumping.

Rearing: A sudden postural change in a horse so that it stands only on its hindlegs. Rearing is both an innate anti-predator manoeuvre and an intraspecific social behaviour, usually between stallions or colts. Habitual rearing in horses usually accompanies other conflict behaviours.

Refusal: A conflict behaviour that is typically associated with the approach to jumping an obstacle during which the horse suddenly stops. A precursor to or a form of napping.

Rein back: A step-back or a series of steps backwards with the legs in diagonal pairs. It is initially trained by the decelerating effects of the reins and later cued via classical conditioning by leg position of the rider.

Reinforcement: The process in which a reinforcer follows a particular behaviour so that the frequency (or probability) of that behaviour increases (Wolpe, 1958; McGreevy, 2004).

Reinforcement schedule: The frequency of the reinforcers used in training the horse by the handler. The schedule may be continuous, intermittent or declining.

Reinforcer: An environmental change that increases the likelihood that an animal will make a particular response, i.e., a reward (positive reinforcer) or removal of an aversive stimulus (negative reinforcer).

Resistance: See Conflict behaviour, Evasions and resistances.

Respect: A term used in general horsemanship and Natural horsemanship that emphasises the significance and relevance of the hierarchy in horse-human interactions. The notion of respect may imply subjective mental states that the horse may not possess. Furthermore, in training and retraining, the concept of respect may encourage remedies for behaviour problems that are unrelated to the original behaviour problem. Thus, from the viewpoint of learning theory, such a concept may be inappropriate and have negative welfare implications.

Rhythm: The beat of the legs within the particular gait. In ideal equitation, rhythm is trained to be self-maintained.

Rolkür: See Deep and round. Round: Synonymous with on the bit.

Round-pen (round-yard) training: The practice of causing a horse to flee forward in a round yard until it offers a desirable response (such as slowing), at which point the sending forward is instantly terminated. This can be interpreted as negative reinforcement. Critics of this technique question the accepted interpretation of the responses of the horse undergoing this process and, in particular, the allowance of fearful behaviour because of its obvious association with humans and the risk of spontaneous recovery.

Running (away): A hyper-reactive state in the horse characterised by acceleration and usually heaviness in the reins. The horse is exhibiting conflict behaviour and attempting to flee the aversive situation. Such states are usually the result of incorrect negative reinforcement and can be associated with conflict behaviour. See Rushing.

Rushing: A horse that is not under the stimulus control of the cues to slow, usually in relation to approaching a jumping obstacle. Often anthropomorphically interpreted as ‘keenness’.

School: a) An enclosed area, either covered or open, in which a horse may be trained or exercised.
b) To train a horse for whatever purpose it may be required. Scope: The range of both the stride patterns associated with the gaits and the ability to spring or jump.

Self-carriage: The way in which an educated horse deports itself. Due to the obtrusive and aversive potential of rein and leg pressures, it is important that the horse travels in-hand and under-saddle free of any constant rein or leg pressure for fear of habituation and/or conflict behaviour. Self-carriage refers to the self-maintenance of rhythm, tempo, direction, straightness and outline.

Shape, frame (US): See Outline.

Shaping: The successive approximation of a behaviour toward a targeted desirable behaviour through the consecutive training of one single quality of a response followed by the next. In horse training, a shaping program is known as a Training scale. Not paying due attention to shaping in horse training has been associated with conflict behaviours (Morgan, 1974; McLean, 2003).

Shying: The sudden hyper-reactive sideways leaping of the horse either from an aversive object it encounters or as an expression of conflict behaviour that has arisen due to unresolved problems in negative reinforcement (e.g., when the contact is too strong). A shy begins with a turning away of the horse’s forequarters followed by an acceleration response. Shying is frequently associated with other conflict behaviours and may be followed by bucking.

Signal: See Cue.

Slow gait: One of the gaits of the five-gaited breeds characterised by a prancing action in which each foot in turn is raised and then held momentarily in mid-air before descending.

Soft condition: Easily fatigued or unfit.

Soft mouth: Sensitive mouth, responsive to bit pressure.

Spinning: A sudden change in direction, akin to shying in origin and expression; it has associations with conflict behaviour.

Spooky: Shys or baulks readily/frequently.

Star-gazer: A horse that moves in-hand or under-saddle in an awkward position with its head elevated, as if looking upwards.

Step: The single complete movement of raising one foot and putting it down in another spot, as in walking, used in equitation parlance to describe the nature of the movement in an individual horse and often erroneously based on observation of the forelimbs only.

Stereotypy: A repeated, relatively invariant sequence of movements that has no function obvious to the observer. A number of stereotypic behaviours are seen in horses and are erroneously referred to as stable vices

Stimulus: See Aid.

Stimulus control: The process by which a response becomes consistently elicited by a signal or cue.

Stimulus generalisation: The reinforcement of a response in the presence of more than one stimulus.

Stop/slow/step-back: The decelerating response in the trained horse that results in it ceasing or decreasing its forward movement in-hand and under-saddle. The stop response is most commonly trained by negative reinforcement, using the bit in the horse’s mouth, stimulated by the reins in the rider’s hands. Classical conditioning converts the stop response to light aids and then to the bracing of the seat. Decelerating involves activation and emphasis of different musculature from that involved in forward motion. These muscles are isolated by the step-back response. Therefore, it is not surprising that training of the stepback trains the stop response. Slowing the horse can occur through shortening the stride or slowing the activity or tempo of the legs.

Straightness: A fundamentally desirable trait in equitation such that the hindlegs move into the line of the fore tracks on lines and circles and the longitudinal axis of the vertebral column is straight. Straightness is necessary in order to achieve maximal biomechanical and motor efficiency in the horse and consequently considered a tenet of basic training (Murphy et al., 2005). When horses are not straight, they tend to drift toward the convex side. Thus crookedness may be seen as a symptom; the deeper problem is that the horse is not following the rider’s (or handler’s) intended line (McLean, 2004).

Stress (acute and chronic): Stress, in its acute form, is a short-term dysfunction of the signal-response relationship presenting variously as raised tension levels, agonistic behaviours, redirected aggression and displacement activities. Chronic stress manifests as raised corticosteroid levels, physiological disturbances, gastric pathology, repetition and ritualisation of original conflict behaviours, redirected, ambivalent and displacement behaviours, development of stereotypies and injurious behaviours, such as self-mutilation and increased aggression (Wiepkema, 1987; Moberg and Mench, 2000).

Stress colic: Abdominal pain thought to be associated with inability to cope with aversive conditions (Hungerford, 1975).

Stride: a) The set of changes occurring during a single complete locomotory cycle that includes the stance phase and the swing phase of a limb, from the one landing of a particular foot to the next.
b) Used in jumping to describe a rider’s appreciation of the number of whole steps a horse takes between obstacles.
c) Medium walk/trot/canter: A descriptive term for strides that are longer than at working paces, but not as long as extended paces. Medium strides are therefore part of the development of longer strides in equitation. For the average horse in medium walk and trot, the hind tracks should land approximately 10 to 20 cm in front of the fore tracks, whereas in medium canter the hind tracks land approximately 1.5 m in front of the fore tracks.

Stubborn: A horse that appears unwilling to respond to the aids, probably due to lack of motivation or habituation to signals as a result of incorrect negative reinforcement.

Submission: See Dominance/submission.

Switch off, tune out: A lack of response to any signal (altered attention and motivation levels) provided by a rider or handler when a horse becomes hyperreactive. This may be an expression of learned helplessness. Switching off and becoming ‘dead to the aids’ is likely to be accompanied by raised corticosteroid concentrations and may be partly caused by state dependent learning, i.e., learning that takes place and is only retained when the internal milieu of the horse is in the particular state at the time of learning. When this state shifts, memory and learning may be reduced or absent. There are training implications associated with this concept if horses are trained only when they are calm.

Tail swishing: Lateral and dorsoventral movements of the tail symptomatic of conflict behaviour in hyper-reactive horses. In the absence of other irritants, tail swishing can be a clue to incorrect negative reinforcement of the go response or indicate a dislike of too-tight reins and unrelenting leg/spur pressure.

Teeth grinding: In the absence of dental or other health disorders, grinding the teeth is a response to unresolved stressors encountered during training, or a product of general management. It may be associated with incorrect negative reinforcement of the stop/slow/step-back response.

Tempo: The timing or rhythm of the horse’s strides.

Tension: In equitation, hyper-reactivity and presumably heightened HPA axis activity. Tense horses are frequently hollow and show various behavioural indicators of stress.

Tilting nose: A posture adopted by some horses during locomotion under-saddle such that the nose tilts to one side. It results from incorrect negative reinforcement, principally during the training of the turn response (no release for the correct response or pressuring for the turn when the inside leg is on the ground and unable to respond) but also in the training of the stop response (no release and contact too tight).

Track up, overtracking: Associated with engagement of the hindlimbs to the point where the foot fall of the hindlimb reaches forward and overlays or surpasses the print of the ipsilateral forelimb.

Trailing hindquarters: In equitation, the action of the hindlegs such that, at the moment of thrust, the hind hooves are not underneath the hocks but behind them. The horse is said to out behind and is usually also hollow. This prevents the horse from attaining impulsion and collection.

Training scale: A progressive order of training particular qualities of responses through the process of shaping. Shaping programs merit further research.

Transition: The change from one gait type to another, or from one stride length to another. A transition can be between gaits, within a gait or from one tempo to another as well as into and out of the halt.

Tune out: See Switch off.

Turn: A change in line of locomotion by the horse. The turn is initiated by the forequarters with the hind feet following the fore tracks. Turning occurs through shifting the inside leg slightly to the side, decelerating it on contact with the ground, and accelerating the opposite foreleg in contact with the ground. The turn is trained by negative reinforcement using the stimulus of the single rein, which classically conditions to the light rein aid and then to cues of associated changes of the rider’s position at the initiation of the turn. The turn aid should be applied when the turning leg is beginning to go forward.

Unlevel/uneven: A euphemism for abnormal action caused by either clinical lameness or a physical abnormality that changes the action of the horse.

Working trot/canter: A term that refers to the normal stride length within the gaits. In the working trot the stride length is where the hind feet land into the fore tracks. In the working canter the hind tracks land approximately 1 m over the fore tracks. There is no working walk in equitation; the basic walk is the medium walk, such that the hind track lands in front of the fore track.

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