Biomedical Engineering Reference
In-Depth Information
did not come into common use until after enactment of the
AWA and its regulations (see below), the academic roots for
the empirical evaluation of the welfare of captive primates
were evident many years earlier. Much of the early work on
enrichment and behavioral management began in zoos and
included nonprimates as well as primates. Hediger
(
Hediger, 1950, 1969
) wrote of the need to occupy captive
animals with play and training and the need for captive
animals to behave in ways similar to their wild counter-
parts. However, as early as the 1920s, Yerkes (
Yerkes,
1925
) wrote about the need to design apparatus that would
allow captive apes to work or play. Beginning in the 1970s,
Markowitz initiated a series of empirical studies to improve
zoo animal environments using what would now be called
enrichment techniques (
Markowitz, 1975, 1982
). In 1979,
an edited volume, Captivity and Behavior: Primates in
Breeding Colonies, Laboratories and Zoos (
Erwin et al.,
1979
), focused on understanding a variety of behavioral
issues affecting captive primates, including abnormal
behavior, attachment, aggression, and enrichment. Several
topics and hundreds of peer-reviewed scientific articles on
behavioral management and enrichment have been pub-
lished since that time. Some of these resources for envi-
ronmental enrichment are provided in
Table 6.1
.
Today, providing for the psychological well-being of
nonhuman primates (NHPs) is an integral part of animal
care. Facilities housing NHPs for research or exhibition
devote substantial resources in an effort to meet the
behavioral needs of their animals, and all such facilities in
the USA must by law have an Environmental Enhancement
Plan in place (
USDA, 1991
). Many institutions, including
all of the National Primate Research Centers in the USA as
well as other breeding and research facilities, have behav-
ioral management units dedicated to providing for the
psychological well-being of the NHPs. The majority of
these units are overseen by PhD-level behavioral scientists
or veterinarians (
Baker et al., 2007
). These behavioral
management units typically are responsible for determining
the enrichment plan for the facilities, socializing primates,
training NHPs to cooperate with clinical or husbandry-
related procedures, training caregivers, and conducting
behavioral assessments. Specialized positions in behavioral
management are now commonplace in research facilities,
substantial budgets are devoted to the behavioral manage-
ment of the NHPs, and commercially available products
have been designed and marketed to promote the psycho-
logical well-being of NHPs.
This chapter summarizes a number of concepts that are
integral to the appropriate behavioral management of
laboratory primates and to the promotion of their psycho-
logical well-being. We will focus on the NHPs most
commonly utilized in biomedical research, including
macaques (i.e. rhesus macaques (Macaca mulatta), cyn-
omolgus macaques
macaques (M. nemestrina)), baboons (Papio spp.), and
New World species, such as marmosets (e.g. Callithrix
spp.), owl monkeys (Aotus spp.), and squirrel monkeys
(Saimiri spp.). The concepts discussed here clearly apply to
other NHP species as well.
DEFINITIONS OF TERMS
Four important
terms used repeatedly throughout
this
chapter
environmental enrichment, behavioral manage-
ment, psychological well-being, and welfare
e
are some-
times used interchangeably; such usage is inappropriate
and can be confusing. Enrichment has been defined as “an
animal husbandry principle that seeks to enhance the
quality of captive animal care by identifying and providing
the environmental stimuli necessary for optimal psycho-
logical and physiological well-being” (
Shepherdson, 1998
,
p. 1). Enrichment should influence multiple aspects of an
individual's behavioral repertoire. It is often classified into
five broad and overlapping categories (
Bloomsmith et al.,
1991; Keeling et al., 1991
): social enrichment and four
types of nonsocial enrichment that typically consist of
physical, sensory, food, and cognitive/occupational
components. Although this definition implies a broad focus
on multiple behavioral dimensions, in practice the term
“enrichment” is sometimes simply used to refer to toys and
objects given to animals. Partly due to this misuse of the
term “enrichment,” many professionals working with
captive nonhuman primates now prefer the broader term
“behavioral management.”
Behavioral management is a comprehensive manage-
ment strategy (
Keeling et al., 1991
) that includes using
enrichment (both social and nonsocial), positive reinforce-
ment
e
training, facilities and enclosure design, positive
staff
animal interactions, and behavioral monitoring to
promote psychological well-being (e.g.
Bloomsmith and
Else, 2005; Weed and Raber, 2005
). Behavioral manage-
ment is a holistic approach to captive care with the aim of
increasing the animal's opportunities to express species-
typical behaviors and decreasing the occurrence of
abnormal behaviors. An important advantage of this
approach is that the individual tools of enrichment, social-
ization, training, and environmental design can be inte-
grated to achieve behavioral goals for captive primates more
completely than any single technique applied in isolation
(
Whittaker et al., 2001
). The goals of behavioral manage-
ment are to have animals that are in good physical condi-
tion, display a variety of species-typical behaviors, are
resilient to stress, and easily recover (behaviorally and
physiologically) from aversive stimuli (
Novak and Suomi,
1988
). These goals should be addressed throughout the
entire life span of the individual, and not just the time
during periods in which the individual
e
is a subject of
(M.
fascicularis),
and pigtailed
a research study.
