Download Paarden: vrijdag 29 April

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”.
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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-
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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
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