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Paarden: vrijdag 29 April An accurate diagnosis is an essential prerequisite to the successful treatment of any behaviour problem and a veterinarian must be involved in either ascertaining ascertain the diagnosis. This lecture focuses on equine behavioural modification techniques. The therapist must have a clear understanding of how horses learn as the behavioural modification techniques are based on an application of learning theory. Learning is a relatively permanent change in behaviour resulting from experience (1). However a change in behaviour is not necessarily the result of learning. There are internal mechanisms that may result in a short lasting change in behaviour, such as, exhaustion, hormonal influences, hunger and thirst. Learning allows animals to adapt to their environment and it is this ability of the horse to learn, which allows us to ride or harness them or otherwise work with them. If we do not understand or abuse the way in which horses learn, behavioural problems will most likely ensue. Horses have the clear ability to learn by association and non-association. Association learning involves operant conditioning and classical conditioning. Operant conditioning forms an association between behaviour and a consequence for that behaviour. Operant conditioning. 1. Positive reinforcement: Here the horse makes the association with the performance of a certain behaviour and a consequence (deliberately presented in a training situation or incidental) which results in the increase in the performance of that behaviour. For example, giving of a food treat (reward/reinforcer) after a horse has performed a command. 2.Negative reinforcement: In this case the removal of a stimulus leads to an increase in the performance of a Abstracts European Veterinary Conference Voorjaarsdagen 2011 behaviour. For example, leg yielding. The horse moves away from the pressure of the leg and the behaviour is rewarded/reinforced by releasing/ removing this pressure (stimulus). 3.Positive punishment: the addition of an aversive or unpleasant stimulus to reduce the likelihood of the performance of a behaviour. For example, smacking, slapping, whipping, punching, and kicking a horse for the performance of an unwanted behaviour. 4.Negative punishment: the removal or withholding of a pleasant stimulus to decrease the likelihood of the performance of a behaviour. For example, removing a horse from an enclosure where its comrades are present. There are numerous problems associated with the use of punishment (2), for example, punishment: • is nondirective, suppressing but not enhancing alternative behaviours; • has the potential to desensitise an animal to the punishing stimulus if the punishment intensity is not optimal; • carries the risk of deleterious emotional changes that can interfere with attention and learning; and • may be associated by the animal with the person delivering it. Because of the damaging effects of its incorrect use, punishment should be used only when other avenues have been exhausted and is best used in conjunction with an antecedent secondary punisher (such as the word ‘No!’) so that the primary punisher itself can be eliminated at some stage (2). Classical conditioning is a form of associative learning that was first demonstrated by the Russian physiologist Ivan Pavlov. While researching digestive function in dogs, Pavlov observed that dogs would salivate prior to attaining food. In a series of well-known experiments, he presented a variety of stimuli before the presentation of food, eventually finding that, after repeated association, a dog would salivate to the presence of a stimulus other than food. He termed this response a conditional reflex. A typical response with regards to horses is their reaction to the sound of the food bin or the response of riding school ponies to the riding instructress saying “trrrrrot”. 1 CHAPTER 5 T r e at i n g e q u i n e b e h av i o u r p r o b l e m s – t h e v e t t e c h ’s p e r s p e c t i v e ! V. Jonckheer-Sheehy MVB MRCVS MSc LAS CertWEL Department of Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University The Netherlands Clicker training uses a combination of secondary positive reinforcement where the secondary reinforcer (the click) has been classically conditioned to a primary reinforcer such as a food reward. Non associative learning is discussed below under habituation. Equine Behavioural Modification Techniques 1. Prevention of: a. Exposure to the stimulus/context: The stimulus or context which cause the abnormal behaviour or in which the abnormal behaviour are performed may be removed or changed so that the behaviour is no longer performed by the horse. For example, the use of blinkers b. The performance of the problem behaviour: For example, prevention of crib-biting by placing a restrictive band around the neck of the horse which restricts the action of the muscles in the neck or by surgically cutting the muscles in the neck to prevent their action. However, preventing the performance of these coping behaviours will cause stress because the horse will remain stimulated to perform them as the stimulus has not been removed (3). 2. Habituation Habituation is a form of non-associative learning and is the process in animals in which there is a decrease in psychological and behavioural responses to a stimulus after repeated exposure to that stimulus over a period of time. Habituation introduces a horse to a stimulus such as the presence of a particular person (such as a veterinarian or farrier), procedure (such as clipping, vaccination or deworming) or object in order to gain the horse’s acceptance of the stimulus without fear. a. Systematic desensitisation The horse is initially exposed to a partial stimulus which does not elicit a fear response, i.e. a much milder version of the original fear eliciting stimulus. Step by step the stimulus is increased until the horse can be exposed to the full fear eliciting stimulus without showing a reaction. It is used for example in gentling, sacking-out, clipper training, injection shyness etc. It is widely used in combination with coun- 2 ter-conditioning to raise the threshold at which an animal reacts to something, i.e. used to control a variety of forms of arousal including fear. b. Flooding Flooding is exposure to full intensity stimulus while restraining or confining the animal until the animal stops reacting. Flooding is not without risk to the horse, people involved in the process and other property in the vicinity. More importantly although the procedure may possibly result in quicker results then when using systematic desensitisation welfare is greatly compromised during the procedure and if it is incorrectly carried out the behaviour will be worsened due to sensitisation. 3. Counter-conditioning Counter-conditioning is the process whereby an animal is trained to respond in a way that is incompatible with the response which is to be eliminated, when presented with a problem-evoking stimulus: a. Classical or respondent counter-conditioning Here an unconditioned response as the desired response is used. For example, this could be the sound of a person clapping their hands twice or a whistle being blown before getting a highly valued food item such as apples or carrots. The sound now predicts the horse attaining a treasured food source. Once the response has become reliably established the sound can be used to gain the horse’s attention when a potential problem situation arises such as the presence of an unfamiliar dog or horse. b. Operant counter conditioning This is also known as counter commanding and response substitution. Here a conditioned response is used. For example, horses that barge when leaving the stable or horse trailer/box. Standing the horse in a neutral environment while being tied up is reinforced with a high value food source. The handler uses a key word such as “stand” or “still”. The horse will soon learn to associate this word with the behaviour. This behaviour is a conditioned response of standing still. Desensitisation in association in combination with counter conditioning are very commonly used to treat aggression and anxiety related problems. Abstracts European Veterinary Conference Voorjaarsdagen 2011 Paarden: vrijdag 29 April 4. Overshadowing Overshadowing is a process that occurs when two stimuli of different strengths are applied simultaneously to a horse with the stronger stimulus overshadowing the weaker one. This results in attenuation of the weaker stimulus and may explain why decreased responsiveness and conflict behaviours in some horses can result from the application of two concurrent aversive stimuli. It is useful in clippers training, treatment of girthing problems and fear of aerosols or needles (4). It is commonly used in the training of police horses. ment and management of its behavior. Cambridge: Cambridge University Press, 2005. 4. McLean AN. ‘Overshadowing: A Silver Lining to a Dark Cloud in Horse Training’, Journal of Applied Animal Welfare Science, 2008:11(3):236 — 248. 5. McGreevy P. Equine Behaviour: A guide for veterinarians and equine scientists. Philadelphia, PA: Saunders, 2004. 5. Shaping Shaping is the concept of reinforcing successive approximations to the final response allowing a trainer to move from a situation where it is impossible to reinforce a desired response (because that response never occurs) to one where the response is occurring, being enforced, and increasing in reliability (5). Kayce Corver SATS method is based on shaping. Shaping is used in almost all behaviour modification processes. 6. Modification of the motivation The underlying motivation for the behaviour may be modified by medication, surgery and environmental enrichment strategies. The most important of which is environmental enrichment, which is often used in the treatment of stereotypic behaviour. Psychopharmatherapeutic agents are much less commonly used as a n adjunct to treatment of equine behaviour problems as compared to dogs for example as the scientific literature to support its use is greatly lacking and the safety and efficacy of the drugs in horses is largely unknown. CHAPTER 5 Equine behavioural problems are usually very approachable, however they require time to evaluate and treatment options need to take into account the willingness of the owner, the facilities available and the ability of the horse. References 1. Fiske J. How Horses Learn: Equine psychology applied to training. USA: The Stephen Green Press, 1979. 2. Mills DS. Applying learning theory to the management of the horse: the difference between getting it right and getting it wrong. Equine Vet J Supplement, 1998; 27:44-48. 3. Mills DS. Repetitive movement problems in the horse. In: Mills D, McDonnell S. The Domestic Horse: The evolution. Develop- Abstracts European Veterinary Conference Voorjaarsdagen 2011 3