Chapter 14 Handling and transport
Chapter contents
The principles of good handling
Horses are potentially dangerous because of their size, strength and speed. Using the responses that have evolved as part of their agonistic ethogram, they can kick, strike, bite and barge humans as readily as they do conspecifics. Additionally, they may deploy anti-predator strategies, such as charging, on humans.
Working with animals presents various dangers, so animal handling is a critical skill for veterinary students and veterinarians. In an Australian study of 2800 veterinarians, 51% reported a significant work-related injury during their career and 26% reported having an injury within the past year. In addition, large animal practitioners were most likely to have chronic or significant injuries.1 In a similar US study, 65% of veterinarians had sustained a major animal-related injury and 17% had been hospitalized within the previous year.2
In a survey of equine veterinarians in Australia, a list of frustrations with their work included unreasonable and disagreeable clients as well as those who provided inadequate facilities and/or could not control their horses. The risk of injury and the physical demands of equine veterinary work were also listed as distracting from the enjoyment of their career choice.3 From the moment they graduate, junior veterinarians not only have to take responsibility for their own safety but also that of the patient, their personnel and the client. This is a significant responsibility, especially when the patient requires sedation, anesthesia, euthanasia, suturing or is in behavioral extremis (e.g. upside-down in a horse trailer after a road-traffic accident). In addition, animals such as horses can be large, and with size comes greater power. Because horses are flight animals and therefore prone to hyper-reactive defensive behaviors, the danger to human handlers is exacerbated. So horses that are presented to vets can be fractious not only as a result of their disorder but they may also be largely unhandled or, worse, may have acquired dangerous responses to traditional handling techniques. Finally, there may be considerable variation in the safety of facilities, competence of handlers and the extent to which the horse is already primed with adrenaline secondary to trauma, pain or behavioral extremis.
Horses themselves are excellent barometers of handling skills in that they may struggle more and become generally distressed when poorly handled. Those that are handled correctly are easier to both examine and treat. Veterinarians who cannot handle animals are mostly unable to teach their clients how to do so, a state of affairs that clearly leads to an unfortunate spiral with the animal’s health and welfare ultimately suffering. However, handling the patient quietly and efficiently raises the image of the treating veterinarian in the eyes of those present.4
Thus, handling the patient is a fundamental additional aspect of the communication curriculum because building a relationship with the client through his or her animal, by acknowledging and relating to the animal, is a critical element in veterinary consultation models.5 Inappropriate handling can affect diagnostic parameters6 and even play a critical role in a compromised patient’s ability to cope.
Aggressive horses have usually learned that threats and attacks on humans are reinforcing because they effectively reduce the threat posed by the presence of humans. However, learning can be turned to our advantage since, for example, neonatal handling has a beneficial effect on the subsequent general tractability of foals.7
Naïve horses are usually frightened of being handled but are seldom actively aggressive, preferring to avoid contact. (This is central to early roundpen training.) They will be less distressed if they can be handled with educated conspecifics, preferably those with whom they have already had social interactions that have led to the more experienced animal emerging as the leader of the dyad.
The prior experience and temperament of a horse are significant for prospective handlers whether they be riders, trainers, farriers or veterinarians. However, even without a full history or the benefit of an owner to advise them, experienced personnel can predict the most likely response by studying the body language of horses. Regardless of the presence or absence of alarm bells in a horse’s history and warning signs in its behavior, it pays to reduce risks when handling all horses, e.g. by ensuring that during all procedures, equipment and personnel within a stable are kept to a minimum and that personnel remain on the same side of the horse as one another (Fig. 14.1).
Figure 14.1 Hazard reduction should be undertaken before horses are handled. At the very least, personnel should all try to remain on one side of the horse.
Tact and subtlety are the cardinal markers of good horsemanship. Young, naïve and fearful horses demand the greatest tact. Personnel should avoid making sudden movements so that one can clearly identify which responses can be elicited and controlled by a steady approach. Correct handling procedures can lower reactivity levels in horses, and may facilitate learning in some circumstances.8
Since horse handling is commonly based on negative reinforcement (see Ch. 4), it is worth remembering that for as long as force is used it will continue to be needed. It is fundamental therefore that the application of pressure must be followed by release (see Ch. 13). Under ideal conditions this means that just as the pressures applied during the most desirable forms of equitation are minimal, the very least force should be used to lead and control a horse when one is on the ground. It is incumbent on the horse handler to use a minimum of force because each episode of handling represents a learning opportunity. The horse that has learned to struggle and has been reinforced by being allowed to escape is more likely to offer the same behavior in future. Excessive force or the failure to release the pressure when the horse responds appropriately are likely to cause problems related to conflict and habituation.
It is always worth remembering how useful positive reinforcement can be in shaping desirable responses (Fig. 14.2), especially when aversive stimuli have been used previously. For example, horses that are reluctant to load into a trailer (float) can first be trained to approach a target and then the target can be moved to various locations inside the vehicle.9 The lessons learned this way rapidly generalize to novel conditions, such as different handlers and vehicles. A limited-hold procedure and the presence of a companion horse seem to facilitate training.
Figure 14.2 Wither scratching can be used in shaping horses to remain still and can be helpful in calming horses that are in pain.
The use of the voice in horse handling has been both over-rated and under-rated. Horses respond to a handler’s body language and voice. When both are consistent in all handling sessions, the horse’s response becomes increasingly predictable as one would expect with any classically conditioned response. By using the same voice cues when training responses, a trainer can give a horse auditory cues that help to identify the required response (such cues become discriminative stimuli; see Ch. 4). If the human is conversing with the horse, there is the possibility that the horse may habituate to the noise and become reasonably calm if required to do little more than relax. However, the opportunities for associations between a verbal command and a certain response are diminished since the horse is challenged by the need to filter commands out of the conversation. In other words, discrimination becomes more difficult.
Since consistency is the cornerstone of all good training programs, the use of a routine is helpful in early training of basic responses that are fundamental to so-called manners. After these have been instilled, the horse can be trained to generalize the learning from these lessons to other contexts. Among other things, this should include being taught to lead from both sides.
For many vets the pleasure of equine work is somewhat offset by the reality that horses are often very fearful of such practitioners. With their ability to learn quickly from aversive events and their formidable memory, horses can remember individual veterinarians and demonstrate accurate recognition of their colleagues from a given clinic because of uniforms or even more generically because of odors (such as surgical spirit) frequently associated with members of the profession. The increased use of chemical rather than physical restraint may reduce the fearfulness of the average equine patient. At the same time, owners can help by habituating horses to being handled in the way a veterinarian handles them. Following the model offered by puppy pre-schools, it is preferable to do this before rather than after a problem has developed.
The color of clothes worn for handling horses is immaterial when compared with the stimuli horses associate with certain clothing.10 In the wake of reports that synthetic pheromones can modify behavior in other species,11 it is worth considering ways in which odors may be used to calm horses. Perhaps the role of familiar odors helps to explain why horse-lore makes mention of the pacifying effects of rubbing one’s hands on the chestnuts of a horse prior to ‘befriending’ it. On a more scientific basis, early reports of the effects of a synthetic ‘equine appeasing pheromone’ in reducing behavioral and cardiac indicators of fear during a fear-eliciting test (return to familiar conspecifics by parting a curtain)12 are exciting and suggest that horses may be effectively calmed before novel husbandry and training experiences. By the same token it may be that angry and frustrated humans emit characteristic odors in their sweat that signal to horses the emotional states of their handlers and thus increase the horses’ arousal.13 The effects of different handlers on the behavior of horses are sparsely reported, but it has been proposed that by looking for excessive ear movements when horses are led around an obstacle course, one can detect inexperienced handlers.14
Donkey handling
The differences between the behavioral repertoires of donkeys and horses should be considered when handling donkeys and mules. Some of these differences are inherent; for example, donkeys tend to have different responses to fear-inducing stimuli, tending to freeze more readily than horses (a distinct advantage should they become stuck in barbed wire). Other differences are related to the amount of training and human contact experienced by the individual.
When faced with frustrating situations and forced to respond with aggression, donkeys tend to give fewer warning signs than horses. Additionally it should be borne in mind that because of their enhanced ability to balance, donkeys can easily cow-kick. Few donkeys have been taught not to lean when having their feet examined. This makes veterinary examinations of the hooves and farriery generally more difficult in donkeys than in horses and ponies. Despite their agility, restraining most donkeys is straightforward if their head can be controlled. Unlike some other species, such as pigs, all equids follow the general rule of ‘where the head goes, the body will follow’.
Generally, when compared with horses, donkeys tend to have experienced less close human contact because they are less likely to be ridden and, as a result, they tend to be less well trained. For instance, in the absence of any need, they are rarely taught stable manners. On the other hand, it appears that because fewer people are nervous of donkeys, they are likely to have been handled with more confidence (Jane French, personal communication 2002).
Approaching the horse
Until we can, with certainty, unpick the relationship between horses and humans, we are likely to vacillate between explaining a horse’s responses as those used with a predator or with a conspecific. Arguably, horses do not have a concept of predation or their own mortality so much as an ability to categorize other animals as non-threatening and threatening. If horses view humans as a threat, the chances are that their fear responses will be rapidly extinguished if humans do nothing to justify their anxiety. Then it is possible that, during the gentling process, the representation of humans as a threat can be replaced by one of companionship.
The use of the voice can be helpful when approaching equids since it may alert and disarm them. Compared with human clothing, which changes regularly, voices can be a constant cue that assists horses to recognize their owners. As it happens, horse owners tend to use similar calls when calling horses (one of the more common ones being a drawn out ‘come on’). While this can have helpful consequences in horses that are happy to be caught, since they respond by traveling toward the sound, it may alert others to the intentions of the approaching humans and prompt them to move away. In the case of horses that are being retrained to accept being caught, it is appropriate to abandon established cues completely so that new associations can be built.
When attempts are made to corner horses, the same principles of driving and blocking that are used in other herding species, such as cattle or sheep, apply. However, the speed and agility of horses means that this rarely works as a means of catching them. A horse in a confined space may attempt to escape either by scrambling over the fence or turning on approaching personnel to drive them away.
To avoid emerging from horses’ blind spots (see Ch. 2), personnel should always approach them from the side. Convention is that horses are approached from the left. The merit of this tradition may be substantiated by research showing that horses generally use the left eye to observe novel stimuli.15 However, this convention can be revisited in horses that are being trained to extinguish fearful responses associated with handlers. By avoiding staring at horses one may be able to reduce the chances of this being misinterpreted as a prelude to predation or the challenge of a conspecific. That said, there is some evidence from a study of well-handled horses that eye contact does not necessarily affect a horse’s latency to approach humans.16 The speed with which humans move can certainly influence equine responses, e.g. walking quickly past the point of balance at the animal’s shoulder in the direction opposite to desired movement is an easy way to induce an animal to move forward.17
Generally it is helpful to approach an unfamiliar horse slowly in a non-menacing stance, with the body relaxed and slouching slightly. If a penned horse is facing away from the stable door or yard gate, handlers should make noises to encourage it to face them. This prevents handlers from being kicked as they approach the horse and is even considered by some to be an important sign that the horse is showing ‘respect’. If horses ever regard humans as analogous to conspecifics, they could be excused for having problems reading our body language unless we are regarded as issuing constant (and often hollow) threats (because our ears are permanently pinned back).18 Regardless of this, it remains unclear why horses would need to show ‘respect’ to other horses, and therefore submission or subordinance are perhaps more appropriate terms for displays of social deference. That said, most riders want their horses (whether they are companion or performance animals) to be compliant first and foremost, so interpretations of rank may be entirely irrelevant.
Restraint
Once they have begun to exhibit a flight response, most horses that are restrained by the head will continue to struggle until the pressure around the head is released. Horses should be tied up with a secure halter (or headcollar) and rope and never by the reins or a lead attached to the bit. The rope should be tied to a length of bailing twine, which is attached to a solid object. Because it is more readily broken than regular lead ropes and reins, bailing twine is used in combination with quick-release knots in case a struggle ensues. Many serious injuries have been inflicted on both horses and handlers when horses have thrown themselves to the ground in a bid for freedom (Fig. 14.3) or when rails have broken or posts have come out of the ground, so it is important that the bailing twine is weaker than the fixed object to which the horse is tied. Nevertheless, some horse-trainers disagree with this advice since they claim that a breakable connection between the horse and the fixed object actively encourages horses to pull back. The extent of flight responses among horses that are tied up means that the act of releasing horses can be very dangerous, even if they are secured only by quick-release knots. The danger is magnified when more than one horse is tied up and a wave of socially facilitated hysteria crashes over them.
Figure 14.3 A horse that has fallen in an attempt to escape from physical restraint. (The horse was physically unharmed by this incident, but the possibility of it becoming an habitual puller as a result of panic could have been avoided if breakable twine had been used to secure it.)
(Photograph courtesy of Claire Ruting.)
Generally, it is best practice to tie horses at wither height so that normal head movement can be maximized within the limits set by the length of rope between the horse and the fence. This should be such that the horse can turn its head sufficiently to examine objects that would otherwise be in its blind spot, but cannot put a leg over the rope.
There is clear evidence that, as creatures of flight, horses value being able to remove themselves from the threat of discomfort. The danger of horses fighting against physical restraint by blindly paddling their limbs in pursuit of freedom means that hobbles and ropes should be avoided wherever possible. Even under conditions of best practice, rope-burns and even fractures are among the recognized sequelae of roping, strapping and hobbling techniques.
The various roping techniques developed by horsefolk who had no chemical agents with which to pacify horses during aversive interventions have been catalogued elsewhere.19–21 While one cannot deny the inventiveness of the horse handlers who developed these approaches, the necessity that bred it may have passed. While it may be convenient to keep a horse still and safe for a given procedure, the crudity of these forms of physical restraint should be questioned in the light of current thinking about analgesia in companion animals. There is no justification for allowing animals to undergo pain.22 Ethically, one could argue that psychological threats are as aversive as pain itself. By the same token, there is no justification for allowing horses to fight against physical restraint when there is no evidence that they can predict that the episode will ever end.
If, during a handling procedure, a horse is not likely to learn good associations with personnel, there is a very strong argument for avoiding it learning anything. In practice, while emergencies may necessitate using physical restraint before veterinary assistance arrives, chemical agents are indicated more often than force. It is inevitable that some veterinary interventions with horses will be painful, so some level of physical restraint is usually needed to control equine patients, even if it is only to allow administration of chemical restraint. Since horses show a peak in plasma beta-endorphin concentrations23 (and so are likely to be least sensitive to noxious stimuli) in the early morning, it has been suggested that this may be the preferred time to undertake elective aversive procedures.13
The natural inclination of horses to run from trouble makes them difficult to deal with in the open. Although attempts are sometimes made to hold horses in a corner of a field or yard for interventions, horses are usually much safer in a stable, especially one with enough bedding on the floor to prevent them slipping. Anything that may get in the way during a struggle or a forced retreat by the handler, most notably water buckets, should be removed from the stable before any invasive handling or veterinary procedure. Stables with low ceilings are sometime helpful when handling horses that are inclined to rear or have learned to throw their heads up to avoid a twitch. Ceilings suitable for this application have no projections (such as jutting beams) from them that might damage a horse’s head or neck. The presence of the ceiling prevents the horse from gaining momentum as it swings its head up. Though the horse might throw its head up once, it is likely that it feels the ceiling with its ears, and rarely bothers a second time. Rectal examinations may be safely carried out by working round the side of a door. Temporary stocks can be built by placing bales of straw around the horse’s hindquarters.
Equipment for restraint
For most veterinary procedures all that is needed is a reliable attendant to hold the horse firmly with a halter and reinforce appropriate behavior by stroking the animal in anatomical areas associated with stress reduction, including the forehead, neck and withers. Cupping a hand over a horse’s eye on the side on which it is being treated is often very helpful, especially for needle-shy horses (Fig. 14.4). Tying horses up for aversive procedures is inadvisable since their tendency to fight against such restraint usually precipitates an attempt to flee and ultimately increases fear and the likelihood of damage to equipment or, worse still, injury to themselves or personnel.
Figure 14.4 A hand cupped over the eye of a horse can reduce fearful responses to veterinary personnel.
(Reproduced from Rose & Hodgson.21)
Physical restraint should not be used in ways that directly compromise horse welfare. When increased restraint is required, hobbles, a tail rope or service hobbles (see Fig. 12.5) may be used, but these should be seen as emergency measures rather than routine approaches. Horses may be controlled completely by being cast and tied with ropes, but this is rarely necessary since the same result can be achieved more readily by methods of general anesthesia. Occasionally it is suggested that a twitch or rope gag, often found useful when dealing with the hindquarters of a fearful horse, may work by distracting the animal. This is something of an understatement since, at least in the short term, the distraction is pain. However, the pain may be rapidly modified by endorphins.24
The twitch
A time-honored method of restraining horses is to apply a constriction to the upper lip as a so-called twitch (Fig. 14.5). It has the merits of being simple, effective and easy to apply, and is comparatively safe for the horse and the operator. For mildly painful, brief procedures, a twitch will give some added security. It certainly has a place in the protocol for nasogastric tubing of many horses since it seems to reduce their ability to flick the advancing tip out of the esophageal sphincter (Ken Sedgers, personal communication 2002). Twitches come in a variety of forms, from a simple loop of rope attached to a bull’s nose ring, through to a pair of metal pliers called the humane twitch (because it may be associated with less tissue damage in the hands of a novice than a homemade twitch). As with any means of applying pressure, the narrower the element that makes contact with the horse the greater the chances of pain and even permanent damage. Twitches with soft, thick rope and light (i.e. plastic) handles are generally safest. Snaring as much of the upper lip as possible when applying a twitch seems to increase its effectiveness and reduce the chances of it slipping. The constriction should be loosened every 15 minutes or so to maintain perfusion of tissues distal to it. Additionally this is sound practice since the effectiveness of the twitch tends to wane after this period in many cases.
Twitching the lip is an approach that should be adopted only when chemical restraint is not available and is best regarded as a last resort of restraint justified only by a bid to inject a psychotropic drug. In very difficult horses, the ear can be grasped transiently (Fig. 14.6) as a brief means of controlling the horse while a twitch is put on the upper lip. Twitching the ear should always be avoided as it may scar the skin, paralyze the ear or make the animal head-shy.13
Figure 14.6 Grasping of the ear can have unwelcome long-term behavioral consequences and should therefore only be used with caution.
(Photograph by Vince Caligiuri, reproduced by permission of the Sydney Morning Herald.)
The central mechanism (thought to be mediated by beta-endorphins) by which the twitch is believed to work is discussed briefly in Chapter 3. However, regardless of the pathways involved, there is little doubt that the twitch works because it hurts.25 Horses undergo a transient increase in heart rate when twitched.18 Intriguingly, heart rate returns to baseline values more rapidly in the crib-biters than in normal horses.26 Also crib-biters are reported to be less reactive to being twitched than normal horses, being more likely to remain calm.26 This has prompted the proposal that twitching be used to detect covert stereotypers,27 but more empirical data are needed before the management or fate of horses should rest on responses to such a crude intervention.
Broadly speaking, the effects of a nose twitch can often be achieved by ‘twitching’ a generous fold of skin on the side of the neck (Fig. 14.7). Using this technique, handlers can often restrain fearful horses well enough to facilitate the administration of injectable forms of restraint.
War bridle (or rope gag)
A rope or chain passed over the poll and under the upper lip and then threaded through a loop at the side of the face to form a running noose (Fig. 14.8) acts in a similar way to a twitch when pulled tight. Many variations on this theme arise in the literature and are sometimes even advocated for problems in the ridden horse, even though they are simply vehicles for escalated force and should therefore be avoided. A piece of rubber tubing slipped over the portion of the rope that presses on the under part of the lip reduces any risk of injury and does not seem to interfere with the device’s effectiveness. The appealing claims made for the efficacy of commercial versions of this device (e.g. Stableizer®) in calming horses even when ridden suggest that its function deserves scientific scrutiny.
Service hobbles
These are designed to limit a mare’s ability to kick the stallion during mating. They also offer some protection to veterinarians performing rectal or vaginal examinations (see Restraint of hindlimbs, p. 316), though a physical barrier is more usual for this purpose. Various patterns of service hobbles have been described elsewhere in horse-management literature. All limit the motility of the hindlegs by attaching them by ropes to a band around the horse’s neck and most are fitted with some form of quick-release device. Because they occasionally cause horses to fall (usually while struggling) they should be considered for use only in combination with deep, soft bedding materials.
Restraint of the head
Generally speaking, horses are not dealt with unless some harness is put on the head. If a horse darts forward, experienced handlers can hold their ground, with the benefit of a pair of strong gloves, and pull the horse’s head toward them to arrest the horse’s forward movement. An excitable, reactive or flighty horse is best controlled if the handler is standing caudal to the horse’s head and cranial to its shoulder. With this approach, any horse can be controlled in an open space as its momentum can be thrown off course by a sharp tug on the lead rope. When applying this technique, one should keep in mind that the horse’s rump will tend to swing out away from the handler, exposing it to the possibility of collision with objects to the side. Equally, the maneuver brings with it the risk of the horse being placed in an ideal position to rear, strike or bite the handler. The use of a horse rug slung around the cranial pectoral region as a barrier to striking forelimbs has been proposed,21 but the associated risk of the horse becoming entangled by the rug as a consequence of a flight response means that this approach has limited appeal.
It has been suggested that simply lowering the head may have a pacifying effect on horses (see Ch. 13).28 Lowering the height of a horse’s head relative to the thorax has been shown to decrease mean arterial blood pressure.29 Additionally, some studies have noted that certain behavioral states, such as resting30 and relaxation,31 are associated with head lowering. McBride et al.32 reported that behavioral responses of horses to massage included lowering the head. However, most of these studies have been conducted on horses at liberty and therefore have not investigated the effects of pressure-mediated head lowering as a training intervention. A number of researchers concur that a lowered head position is the postural opposite of a recognized signal of alertness.33 However, head lowering should be considered in context, e.g. stallions will lower their heads when ‘snaking’ mares.34 It has also been described as a sign of ‘submission’ when meeting conspecifics during35 which licking-and-chewing also occur.36,37 Furthermore, it is propounded that licking-and-chewing in association with head lowering is a sign of the horse communicating with, or being submissive to, the handler.38,39 That said, there is little evidence that forced head lowering assists in calming an aroused horse in training. Contrary to popular belief, there seems to be no association with licking-and-chewing and head lowering, or with these behaviors and response acquisition.40
A halter is designed to be placed on the horse from the near side. It should be tight enough to prevent the horse from removing it, and the nosepiece should not rest below the nasal bone. The noseband should be loose enough to allow the horse to open its mouth and chew. When designed to allow tightening around the head if the horse resists, this works especially well, in the right hands, within the pressure-release framework (see Ch. 13). However, it is often knotted to prevent it becoming dislodged should the horse struggle. This safety measure often does little to improve the halter’s usefulness because few handlers seem to understand the importance of releasing pressure immediately to reinforce leading responses. As discussed in Chapter 7, it seems likely that there are left- and right-handed horses, so although horses generally lead better from the near side, this is simply because this is what they are accustomed to. By leading horses from both left and right, one can determine whether one side suits the horse better.
A headcollar is stronger than traditional rope halters but does not pull tight. Although the straps that comprise a headcollar give alternative hand-grips for the attendant, best practice is to attach a rope so that, if the horse throws its head up violently, control is not completely lost (since the attendant has a length of rope to pay out). Consistent pressure-release conditioning (as explained in Ch. 13) quickly trains horses, by applying exceptionally subtle downward tension on the lead rope, to lower their heads. As with all pressure-release training, simply pulling until a response occurs is contraindicated since this leads to habituation. Instead, it is necessary to escalate the pressure until a motivating pressure is being applied. Ropes should never be wrapped around the hand or fingers because serious injuries can occur. If the horse snatches its head back with such speed and force that the handler finds it impossible to let go, skin burns and even fractured bones may result.
If the mouth is not being examined, a bit and bridle may be used for restraint. When considering the effect of different pieces of tack, the broader the area in contact with the horse the less discomfort it causes and the less readily it can be used in the negative reinforcement paradigm. This is why horses can easily be trained to pull against harnesses, breast-plates and collars used on well-muscled areas, such as the shoulders and pectoral regions, but are reluctant to fight pressure from bits in the mouth (especially if they make contact only in small areas as is the case with the bladed and twisted bits). When used only occasionally, chains in the curb groove or in the mouth are likely to have a strong effect, especially in the short term. Anti-rearing bits usually have reasonably fine elements and therefore a more severe action than normal riding bits, such as a regular snaffle. Working on several parts of the mouth, these bits help to control particularly reactive animals such as naïve youngsters that may readily toss their heads (Fig. 14.9) and stand up on their hindlegs, but they must be used with sensitivity. Again, the emphasis should be on using light pressure that is released as soon as the desired response has been made. They should never be used in attempts to punish a horse, e.g. by reefing on a lead rope. The inverted ‘port’ on many anti-rearing bits makes them more severe and potentially more harmful than many handlers seem to appreciate.
Restraint of forelimbs
Roping techniques are mentioned in this book only for use in emergencies that arise in the absence of veterinary support. Interested readers can find detailed accounts of such techniques elsewhere.41
During a veterinary examination of a potentially fractious horse, movement and risk of being kicked can be decreased by restraining one of the forelimbs. An additional purpose of raising the forelimb arises when injecting it, e.g. for a peripheral nerve block. A forelimb can be lifted and the hoof brought up to the height of the horse’s elbow and held there by a handler. When holding the forefoot of a horse in this way, handlers must avoid teaching the horse to lean, because this defeats the object of transiently disabling the horse. A light grip on the foot is desirable, but it is important to avoid giving the horse an opportunity to snatch the foot away, which often happens before a horse kicks out at the veterinarian. After due consideration of the hazardous responses it can evoke (especially in naïve horses), the use of a ‘knee strap’ placed around the forearm and just proximal to the fetlock may be considered to hold the leg off the ground. A soft surface underfoot, such as deep bedding, is a prerequisite for this approach because many horses fall before learning that stoicism is the preferred response when normal locomotory responses are compromised in this way. Generally speaking, however, chemical restraint is the preferred option.
Restraint of hindlimbs
Hindlimb hobbles are often used on mares during mating (see Fig. 12.5) or pregnancy testing. Each hindlimb is attached to a collar around the horse’s neck so that the horse can move the legs forward but not backwards. The straps around the pasterns should be made of soft but strong material, such as leather, that is unlikely to burn the horse’s skin. The collar must be of sufficient width to prevent undue pressure being concentrated on a small region of the neck.
Farriers and horse breakers sometimes teach a horse to pick up a hindleg by a modification of the breeding hobbles. A strap is placed around the horse’s hind pastern and a rope attached to the strap. The rope is then run through a padded collar placed around the horse’s neck. The rope may be run back through the strap (if the horse’s leg can be approached), and then pressure on the pulley system lifts the hindleg off the ground. For horses in a situation where the hindlegs cannot be handled (i.e. in the absence of veterinary support), a slip loop can be made in the end of the rope and placed on the ground. The horse is then walked over the rope so that the targeted hindhoof is located within the loop. The rope is then pulled so the loop tightens around the pastern. Once the rope is through the collar, it is shortened until the horse’s leg is at the required position. Unfortunately, rope burns may arise at this point, so the use of a soft rope is critical. The rope is then secured so that the handler can approach and handle the hindlimb safely. Because it is akin to one method of casting a horse, it is unsurprising that, when undergoing this method, many unhandled horses throw themselves on the ground. For this reason the procedure should take place only in a safe paddock arena with a soft landing (e.g. a roundpen containing deep sand). The extent to which the horse also undergoes learned helplessness in this situation is worth considering. With horses that have thrown themselves to the ground, it is said that holding the nostrils closed is an effective means of getting them to struggle to get to their feet. However, adding asphyxiation to the woes of a restrained horse may be ethically questionable.
Donkey restraint
Some donkeys tend to move towards negative stimuli,42 and this may help to explain why they have been found useful in guarding other species, such as sheep, from predation by dogs.43 Being less inclined to flee, donkeys are regarded as stoical, but this reflects a higher threshold to respond, not necessarily a higher threshold for pain or, for that matter, fear. This must be borne in mind when practitioners weigh up the apparent need for chemical restraints in donkeys.
While a horse’s first response is to flee and, if it cannot, to rear and kick, donkeys more usually freeze and simply stand their ground when confronted by aversive stimuli. As a result they have attracted a reputation for being difficult to force into situations. Indeed, it is often the case that the more a handler tries to push them, the more forcefully they will move towards that person.42 Since donkeys cannot easily be forced towards hazards undetected by riders, their resolve makes them safer than horses as riding animals in certain sorts of terrain. If donkeys become entangled in wire or rope, they do not thrash about like horses and so are far less likely to injure themselves, e.g. injuries from barbed wire are less frequent in donkeys. By the same token, when tied securely, to the point at which they accept that they cannot leave, donkeys usually accept most veterinary procedures.42
It is important to note that the twitch is far less effective on donkeys. It is said that it can do no more than distract them from aversive procedures and may do so only transiently before they lower their heads and attempt to drag their handlers away.42 This is especially likely to be an effective and therefore learned evasion in mammoth breeds.42
In cases of lameness, the stoicism of donkeys may make them challenging patients when veterinarians use hoof testers to locate a seat of pain. Foot-care in donkeys presents other interesting challenges because they are so sure-footed and therefore dislike having their balance compromised. This is why they are more likely than horses to refuse to pick up a foot or, if they do oblige, to snatch it back or lean on the handler. One solution to leaning and snatching during foot-care is to capitalize on the tendency of donkeys to accept physical restraint, albeit after a struggle. So, using quick-release knots, one can tie the patient up short and use a sideline for a hindleg and an over-the-back rope or elbow strap for a foreleg.42 Most importantly, before the foot-care procedure commences, the donkey should be allowed time to test its predicament and convince itself that it can stand on three legs. It should also be taught this lesson separately for each leg, since donkeys do not appear to automatically transfer to the remaining limbs acceptance of the tying up of one leg.42
Chemical restraint
The innate inclinations of horses to react strenuously when control is applied is sometimes referred to as ‘opposition reflex’. This explains in part the escalation of force that is required when horses are said to panic. It is always preferable to use drugs to modify a horse’s behavior than to use force. Just as pre-operative analgesia reduces the need for sustained post-operative analgesia,44 so reducing fearfulness seems to reduce the need for sedation. The psychological state of the animal before administration of tranquilizers may markedly affect the degree of sedation achieved. Animals that are intractable and in a state of excitation are likely to need very high doses before becoming manageable, so for routine procedures such as clipping, owners are well advised to avoid a struggle of any sort before the administration of chemical restraining agents. Of course, where the intention is to clip the horse’s hair, the need to avoid sweating makes chemical restraint without any prior arousal especially appealing.
Chemical agents with a variety of pharmacological mechanisms make it possible to alter a horse’s behavior by tranquilization, sedation or immobilization (see Ch. 3). The distinction between sedatives and tranquilizers is reasonably subtle and focuses on the extent to which an agent causes central nervous system (CNS) depression (what would be described in humans as clouding of consciousness). Tranquilizers, such as the benzodiazepines, dissipate anxiety without CNS depression. Meanwhile, sedatives such as phenobarbitone induce a dose-dependent spectrum of CNS effects.45 To complicate matters, the classification of various psychotropic drugs used in horses can also depend on dose, i.e. some tranquilizers, such as the alpha-2 agonists, can cause sedation. Generally, horses are not good subjects for those tranquilizers that cause muscle weakness or ataxia because these outcomes can evoke ‘panic’ responses.46 By the same token, if sedatives are used to produce manageability, high doses should be avoided since these may result in ataxia, depressed response to stimulation and some respiratory depression. Tranquilization during transportation can be dangerous with horses since some react adversely under novel circumstances.47
Transportation of horses
Factors that influence horse behavior and welfare during transportation include:
• preparation of the horse and vehicle
• the extent of social isolation
• sex of, and familiarity with, traveling companions
• previous transport experience of the horse
Although research efforts have focused on road transport, much of the information derived from research into transporting horses by road is also applicable to transportation by sea and air. For many handlers the most unwelcome behaviors arise in their horses during loading and occasionally unloading. Many horses refuse to load and thus add considerable stress to and delays in travel, while a few rush during unloading, sometimes injuring themselves or personnel. Both of these problems should be seen as problems with being led. The case study in Chapter 13 gives a detailed approach to a loading problem. As part of the therapy, the horse is trained to stand still in any spot on the ramp and floor of the vehicle. This rapidly resolves rushing in any direction and is the preferred approach for unloading problems.
Horses brace themselves against and in anticipation of the changes in momentum during road transport by adopting certain body postures (notably the base-wide stance). Panic can arise in horses that have insufficient space to adopt this posture, so in some cases a switch to a wide float is all that is needed to remediate nervous travelers. Efforts expended by horses as they continuously adjust their posture during transit reflect both muscular and emotional stress related to road conditions and the driver’s behavior.48 All of these effects are readily evaluated by monitoring heart rates during transport.48 Horses have been shown to have higher heart rates in a moving vehicle than in a stationary vehicle49,50 and, although heart rates decreased significantly during a road journey, they did not return to resting levels.49,51 Transport stress may increase susceptibility to diseases, including an equine herpes virus 152 and salmonellosis infections.53,54 Other common problems resulting from transportation include traumatic injuries, dehydration and pleuropneumonia. With adequate preparation and care, the incidence and severity of these disorders and their complications can be reduced. Previous experience largely determines the response of the horse to being transported, and it is worthwhile spending time accustoming the horse to the vehicle before transport is required. The calmer the horse remains during loading and transport, the less likely are injuries. Beyond that there is a need for vehicles of strong construction in case horses struggle (Fig. 14.10).
Figure 14.10 Horse that has tried to force its way out of a vehicle. (The horse made a complete recovery.)
(Photograph courtesy of Michael Watiker.)
The longer a journey, the more one can expect to find increases in a horse’s white blood cell count,55 weight loss,56,57 level of dehydration58 and body temperature.59 Body temperatures as high as 39.9°C have been reported in clinically normal horses after a 41-hour road trip.60 Unsurprisingly, with longer road journeys, the risk of horses developing shipping fever also increases.61 A report describing 6 horses following a 9-hour flight noted elevated white blood cell counts, dehydration, and the loss of 4.1 ± 0.8% bodyweight that took 7 days to return to a pre-flight range.62 So it is most likely as a result of the environmental conditions imposed on them during a 39-hour flight, that 7 of 112 horses developed pleuropneumonia (shipping fever) 1–2 days after arrival in one study.63 Air temperature and humidity tend to peak when planes are stationary, e.g. during loading, unloading, refueling and delays. It is important to keep the latter to a minimum.64 Frequent monitoring of rectal temperature is indicated in horses during transit because an elevated temperature is a familiar finding in dehydrated horses59 and may also signal respiratory disease.65
The following discussion will focus on behavioral aspects of transportation and how research is providing data on best practice when horses are transported.
Orientation
When facing forward during transport, horses may incur damage to the head, throat and neck as a result of being propelled forward by braking. Many owners report that traditional forward-facing transportation makes some horses lean back against the rear of the vehicle and sometimes even sit down. In contrast, horses facing backwards are thought to absorb deceleration with their haunches and are better able to maintain stability.66 This explains why rear-facing horses have fewer side and total impacts and losses of balance.67
Several attempts have been made to determine the best orientation of the horse during transport. Untethered horses in transit spend significantly more time facing the rear, and several horses have displayed strong individual preferences for rear-facing orientation during travel.68 Horses facing forward tend to move and vocalize more frequently and have higher heart rates than when facing the rear.51 While Gibbs & Friend69 found no significant preference for facing forwards or backwards, they noted a slight preference for traveling at about 45° to the direction of travel. Some studies have failed to find significant differences in heart rate and plasma cortisol concentrations between horses facing forward and backward during transport.49,67 While this suggests that the imposition of forward-facing travel is not distressing, it does not rule out the possibility that it is tiring and increases the likelihood of injury.70
When a horse with an orthopedic injury must be transported, it should travel with the injured leg to the rear of the vehicle to protect it from the effects of deceleration. So a horse with an injured hindleg should travel facing forwards, and one with an injured foreleg should travel facing the rear. The head should be able to move freely to enable the horse to remain balanced while shifting weight off the injured leg. Horse slings, either commercial or homemade, should be used only in vehicles strong enough to support the weight of the horse in such a manner.71
As horses attempt to balance during changes in speed and direction, they tend to move their heads and feet rapidly. Leg wounds can occur through loss of balance when the vehicle brakes, while traveling around corners, and on uneven surfaces. The most common injuries are to the pastern and coronet.72 The risk of injury can be minimized by the use of protection such as a padded headstall or a poll guard (head bumper in the USA) and protective leg bandages, thoughtful driving and generous tie ropes.72 Bandaging the tail can protect it from damage resulting from repeated contact with the tailgate or wall.
Head position
Equine pleuropneumonia can result from contamination of the lower respiratory tract by normal pharyngeal microflora and has been closely associated with transport. In enclosed containers the respiratory system is often further challenged by increased humidity, ammonia concentrations73 and numbers of airborne microorganisms,74 while in especially dry conditions the mucociliary clearance capacity may be further reduced by desiccation. Depression of cellular immunity may also occur due to stress-induced elevations of cortisol concentrations.74
Horses have evolved to spend long periods with their heads to the ground. Maintained elevation of the head facilitates the introduction of normal pharyngeal flora into the lower respiratory tract and hinders their removal by forcing the mucociliary transport system to work against gravity. When transported horses have their heads restrained, restricted head movement can compromise their ability to both balance and avoid respiratory disease.75 Horses traveling individually in stalls are commonly cross-tied for road transport to stabilize them, but this is not recommended for long-term transportation because it involves elevation of the head. When compared with transportation loose in small groups, cross-tying causes white blood cell counts, neutrophil:lymphocyte ratios and glucose and cortisol concentrations all to become significantly elevated.76
While frequent breaks when traveling help prevent fatigue and dehydration, allowing horses to lower their heads for brief intervals (30 minutes every 6 hours) is ineffective in preventing the accumulation of bacteria and mucus in the respiratory tract.77 In one study,77 at least 8 hours was required to clear the secretions that accumulated after maintaining an elevated head position for 24 hours.
Permitting the head enough freedom to allow the cranial trachea to be below the caudal trachea is the most effective way of preventing accumulations of mucus and bacteria and assisting the mucociliary transport system.78 In a horse that is tied, one method of facilitating this head position and indeed horizontal and vertical head movement is to use a ‘log and rope tie’. This involves passing a lead rope through a loop fixed to the inside of the vehicle and weighting the other end with a block that the horse cannot pull back through the loop.72 Other appropriate measures include lowering hay and food containers, and soaking hay to minimize the inhalation of spores and bacteria.79 It has also been suggested that allowing horses to face away from the direction of travel means that they are more likely to relax and hold their heads down.70
Preventing dehydration
Dehydration is associated with transport because voluntary intake of water during transit is low and, in any case, water is rarely offered during transport. While up to 5% dehydration may pass undetected, even 2–3% dehydration can affect the performance of competition horses.72 Dehydration has also been implicated in the onset of acute laminitis and colonic impaction after extended road travel.72 Horses are sometimes given electrolyte solutions via nasogastric tube to prevent gastrointestinal impaction. Familiarity with and frequency of transport are regarded as important risk factors in colic. Horses that travel one to six times per year have a higher risk of colic than those not transported.72 Interestingly, more than six trips per year are associated with reduced risk of colic.72 It is suggested that this reflects the effect of habituation and correspondingly reduced distress that facilitates adequate drinking and general hydration.72
Breaks in journeys are recommended every 4–6 hours. They offer the opportunity to give the horse some exercise, to allow it to urinate (a response that is strongly inhibited by being on a moving platform), to offer it water and even to give it electrolyte solutions via nasogastric tube if a veterinarian is present. Horses can tolerate 6–8 liters of electrolyte-enriched water by nasogastric tube every 15 minutes, for up to 2 hours if required.72
Studies in hot weather have shown that providing water during transport in summer can have favorable effects on several physiological parameters of hydration and distress.80 Compared with watered horses, unwatered horses showed greater weight loss, higher plasma cortisol concentrations and elevated respiratory and heart rates. Their plasma concentrations of sodium, chloride and total protein, and their plasma osmolality greatly exceeded normal reference ranges, indicating severe dehydration.80
While providing water to group-transported horses (viz. slaughter horses, see below) reduces the incidence of dehydration,81 it is not straightforward because high-ranking horses may prevent others from gaining access to the water. Furthermore, there is a risk of water spillage that would make the flooring more slippery and compromise the horses’ ability to maintain their balance. Providing water on both sides of vehicles and ensuring that bedding is sufficiently absorbent may help to resolve these problems.
Restraint of horses during air transit
The differences between road and air transport are few. In level flight, horses being transported in enclosed containers (Fig. 14.11) regularly doze and rest and their heart rates are close to resting levels.64 Horses seem distressed by movement only during cargo handling, take-off and landing.82 Agitation at these times can include regular changes in body posture to maintain balance and agonistic responses, such as aggression and appeasement.64 Aggression may indicate distress as a result of certain environmental stressors83,84 and is accompanied by increases in heart rate. Fortunately, these episodes do not seem to be frequent or long enough to raise significant welfare concerns.64 They are not accompanied by any changes in hematological or blood biochemical values that would suggest any detrimental effects.82
Figure 14.11 Horse being loaded into an enclosed container for transportation by air.
(Photograph courtesy of International Racehorse Transport.)
Persistent pawing and stamping may be features of some horses’ response to air travel.85 It is interesting that this behavior prior to a race is seen as one of several characteristics of poor performance in racehorses.8 Although rare, the occasional possibility of a horse becoming truly panicked in mid-air merits consideration and forward planning. Even if it may result in the horse being disqualified from competition on arrival, the use of tranquilizers in an airborne horse is preferable to manual restraint.74 With the availability of potent equine psychopharmaceuticals, it is rarely necessary nowadays to euthanase transported horses in emergency situations.74
Transport of horses for slaughter
The welfare of slaughter horses is of concern because inadequate head-room, high stocking rates, poor ventilation, dehydration and long travel times are common. Additionally, the pre-transport condition of slaughter animals is often suboptimal,86 which compromises their ability to cope with transit stressors. It is suggested that even when governments attempt to regulate the conditions under which horses are transported and slaughtered, such rules are often flouted.87 Horses destined for the abattoir are most commonly transported by truck, unrestrained and in groups. A study comparing two densities of horse groups in transit found that more horses fell and more were injured in the higher-density group.88 This reflects the fact that it was more difficult for fallen horses to get to their feet in the higher-density group.88 Horses traveling loose in small groups exhibit less physiological distress than those tied up,75,76 but economies of scale dictate that sufficient individual space is rarely given to horses bound for slaughter. A study of unhandled ponies during road transport showed that more slips, falls, stumbles and collisions occurred at higher stocking rates and that there was less aggression and fewer indicators of poor welfare in group sizes of 4 than 8.89 At lower density ponies tended to align with the pen walls, indicating that these may have offered support.89
Fighting during transportation is a major cause of injuries,86 many of which are incurred during transport through aggression between freshly mixed animals. This may explain why the condition of established bands of feral horses after transport is often better than that of domestic horses from a variety of origins, such as arise in groups of horses traveling from saleyards to slaughterhouses. Clearly, one of the easiest means of reducing such injuries is to avoid mixing horses. Where this is not possible, it is appropriate to separate stallions and particularly aggressive animals from the main group.
Summary of Key Points
• Regardless of whether or not they realize it, good handlers of horses are students of equine behavior.
• By keeping horses as calm as possible, the type of restraint required for current and future handling can be kept to a minimum.
• Horses rarely forget aversive procedures.
• Horses should never be punished for showing flight responses.
• Donkeys respond differently from horses during restraint and veterinary procedures.
• Numerous factors associated with transport can compromise health and welfare.
• Preventing dehydration is a priority in transported horses.
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