Most naïve horses respond to humans as they would to any predator. They behave in ways that help them avoid physical or psychological pressure, by moving away bodily or posturally. These basic evasive responses can be modified successfully to produce a highly responsive equine performer or unsuccessfully to produce a problem horse.

When trainers encounter horses that rapidly enter conflict and as a result do not comply, they often experiment with increased pressure to overcome resistance. Mechanical restraints and stimulants may be used to magnify the pressure that riders can apply. Because of the perceived need to force horses into an ‘outline’ and make them work ‘on the bit’ (see Glossary), the tendency is to use ever-stronger bits as the first approach to solving any resistance. This accounts for the multiplicity of bits on the market. As with any device, it is true to say that if there are many of them available, the chances are that none of them provides all the answers. Furthermore, enlightened trainers recognize that where aversive stimuli have failed to elicit the desired response and have begun to cause behavioral conflict, the application of more force is contraindicated. They rarely reach for such gadgets.

Frustrated trainers often try bits that apply pressure to different parts of the mouth or to the same area of the mouth but with greater severity (Fig. 15.2). Even though they can and sometimes do sever the tongue,⁵ saw-chain bits (so-called mule bits and correction bits) are readily available to riders who are having problems getting horses to respond to milder bits. If changing or increasing mouth pressure is unsuccessful, an alternative or additional means of making the horse adopt the desired shape is to apply pressure to other parts of the head, so training devices such as curb chains, gags, hackamores, bosals, draw reins, balancing reins and chambons may be employed. Unfortunately the tendency is to develop a reliance on these extra pulleys, rather than use them solely for retraining as the name might imply. Martingales and tie-downs are similar in that they apply pressure to prevent evasive raising of the head and are rarely dispensed with.

Figure 15.2 Etching of 18th-century bits. At times it seems that more effort has gone into designing bits than addressing poor equitation.

If the horse fails to show sufficient forward movement or impulsion, trainers direct their attention to the flanks where they can increase the pressure and more effectively drive the horse forward or simply away from the rider’s leg using whips and spurs. Although, for some, these stimulants are distasteful, they are not necessarily contraindicated since they can be used with subtlety and employed transiently to empower the rider’s leg signals. In contrast, tying horses’ heads down (with side reins and draw reins) and clamping their jaws shut with nosebands⁶ are counter-productive in the long term. Indeed there is growing concern that these approaches can automatically compromise welfare by virtue of their inflexibility and inherent absence of pressure-release.⁷

Behavior therapy can help overcome undesirable equine responses that may have an innate component but are largely learned. The temptation may be to treat such traits in isolation. However, a holistic approach has tremendous merit since better results tend to occur if the human–horse relationship is nurtured when the rider is both on the ground and in the saddle. Time spent training horses in-hand seems to pay dividends even in the ridden horse,⁸ presumably through a process of generalization. Achieving stimulus control in-hand seems to facilitate stimulus control under-saddle.⁹ Inter-specific communication may help horses overcome fear and therefore reduce their tendency to use counter-predator responses. It is important that the translation of trained responses from cues in-hand to cues under-saddle is better understood by practitioners. It may simply be that an unconfused horse in-hand is a better prospect for training than a confused one. In any case, correctly identifying the effects of reduced confusion and fear and distinguishing stimulus control from mere compliance may allow us to describe and even measure the bonds that form between horses and their trainers.

By the same token, punishment is regarded by many owners as unenlightened, since it presupposes that horses know the difference between good and bad behavior. So, it is increasingly inappropriate for veterinarians to advocate punishment as a response to undesirable behavior in the horse. It undermines the human–horse bond and carries the risk of injury, which may place any practitioner who advises it in a legally liable position. Examples of acceptable techniques used for behavior modification include habituation and counter-conditioning (see Chs 4 and 13). Habituation is the key to overcoming fear-related responses such as traffic shyness but it can be expedited with counter-conditioning, an approach that relies heavily on the shaping of alternative responses through operant conditioning (see also Fig. 15.3). At its most elegant, equine operant conditioning takes the form of positive reinforcement and subtle negative reinforcement. Consistent use of negative reinforcement is the key to retraining the basics, but is notably more likely to work in horses that have not habituated to pressure. Techniques for restoring sensitivity to pressure cues demand exquisite timing of pressure-release. Meanwhile, clicker training employs positive secondary reinforcement that is particularly useful for refinement of responses, once negative reinforcement has established the basics.

Figure 15.3 Horse being clipped in the presence of food – an example of counter-conditioning.

(Reproduced with permission of Australian Equine Behaviour Centre.)

Horses with innate or learned evasion responses may have the rewarding outcomes of these responses removed by a process of extinction. Furthermore they can be trained to associate the fear-eliciting stimuli with positive outcomes in the same way that laboratory primates can be trained to voluntarily present their forelimbs for intravenous injections. (A case study that required a pony to learn to cope with hypodermic injections appears at the end of this chapter. It followed the injection desensitization training technique developed by ethologists at Pennsylvania State University.¹⁰) A far less humane approach to fearful horses is to flood them by exposing them to an overwhelming amount of the fear-eliciting stimulus in the hope that their responses are exhausted. For example, so-called ‘tarping’, a method of breaking by flooding, involves evoking learned helplessness by casting the horse, covering it with a tarpaulin and beating it until it no longer resists.

Practitioners are strongly encouraged to become extremely conversant with learning theory (see Ch. 4) before counseling owners on the application of these techniques. All of the undesirable responses in the current chapter can be remedied by behavior modification. But a prerequisite is to correctly identify the motivation for a given response. Readers are urged to consider the ethological content of this entire volume when determining causal factors. Beyond that the success of behavioral therapy depends on the consistency of administration and compliance of owners, who must be counseled that the latency for desirable outcomes depends largely on the number of times the horse has trialed and learned from the unwelcome response. With a thorough knowledge of learning theory, practitioners can customize behavior modification programs, modify advice in the light of initial responses and counsel owners when proximate results surprise the uninitiated. So, for example, when as a result of an extinction protocol, undesirable responses become more frequent, the accomplished student of learning theory can explain that this is a manifestation of the frustration effect (see p. 103 in Ch. 4) and that it is transient.