Biomedical Engineering Reference
In-Depth Information
the threshold for intervention for other behavioral problems
(e.g. alopecia or stereotypy) is less clear. As detailed in
Novak et al. (see Chapter 7), it may not be necessary or
useful to try to treat every behavioral problem. Hair loss is
currently one of the most common “problems” dealt with
by NHP behavioral management staff. Because hair loss is
often viewed as an indicator of compromised well-being, it
is a concern for many facilities (
Novak and Meyer, 2009
).
However, as detailed above, not all hair loss has a behav-
ioral etiology (
Novak and Meyer, 2009
). Some facilities
intervene when primates lose more than a certain amount of
hair (e.g. 50%). While such a practice may be useful as
a general rule, it may result in a certain portion of the
population being excluded from receiving potentially
valuable therapeutic interventions (e.g. animals with small
patches of hair loss may respond well to certain behavioral
treatments). However, interventions intended to reduce
alopecia, such as grooming substrates, may be ineffective
for many alopecia cases (
Runeson et al., 2011
). Further,
significant time and effort may be spent providing inter-
ventions to animals that will not benefit from them
(e.g. monkeys that lose their hair coat due to pregnancy). It
is for this reason that empirical research to define behav-
ioral problems and to evaluate potential “therapies” is so
critical. As we learn more about the etiology and resultant
phenotypes of various problems, we can develop hypoth-
eses to determine when behavioral interventions will have
the most impact. As with any behavioral problem, imple-
menting behavioral management strategies that prevent the
problem from developing is highly preferable to attempting
to “cure” the problem once the animal exhibits it, because
many of these behavioral pathologies are resistant
that their studies can be performed with paired or group-
housed NHPs. New cages that allow pairing or pens may
also have to be purchased or built. It is the responsibility of
those involved with behavioral management, as well as of
the local IACUC, to advocate for these changes.
ENVIRONMENTAL ENRICHMENT PLANS
Overview
As previously mentioned, environmental enrichment is
more than toys; enrichment is one of the primary compo-
nents of an effective behavioral management program,
striving to functionally simulate in captivity the most
relevant aspects of the species' natural environment. The
efficacy of a facility's environmental enhancement plan can
be maximized if it adheres to a number of well-established
principles. Enrichment plans should be customized for each
species of nonhuman primate. Different species evolved
under different environmental conditions, resulting in
unique, species-specific behavioral repertoires. Successful
enrichment programs must take these specific behavioral
patterns into account in an effort to increase the biological
functionality of the captive environment (
Newberry, 1995
).
Enrichment programs that are appropriate for one species
may be inappropriate for another (
Lutz and Novak, 2005;
Jennings et al., 2009; National Research Council, 2011
). In
addition, whenever possible, enrichment plans should be
appropriate not only for the species but also for the age and
sex class of the animals involved. Juveniles of many species
tend to be more exploratory and active than adults and
should be provided with more opportunities to explore and
to play. Individuals participating in some types of research
studies (e.g. those that are more invasive or require single
housing) may benefit from supplemental enrichment.
Finally, to be effective, enrichment must be goal oriented.
Whereas the goals of enrichment in general are to provide
opportunities for animals to increase their time spent in
species-typical behaviors and to reduce the amount of time
spent in abnormal or undesirable behaviors, institutions
may have additional goals that apply to the animals them-
selves, including increases in reproductive output or
decreases in trauma due to aggression. Enrichment should
be provided with these goals in mind, and success must be
evaluated and assessed on a regular basis. Items or
approaches that are not achieving appropriate outcomes
should be modified or eliminated.
Enrichment is often applied with the goal of reducing
abnormal behavior. Foraging devices, such as puzzle
feeders or foraging boards, are common interventions for
behavioral issues such as stereotypies (
Bayne, 1991; Lam
et al., 1991; Lutz and Farrow, 1996
). Because the perfor-
mance of most stereotypies and other problem behaviors
are often incompatible with foraging from a device, the
to
change.
It is clear that many factors have been identified that
contribute to the development and expression of abnormal
behavior in captive NHPs. The nursery rearing of infants,
other forms of social restriction later in life, and indoor
housing in relatively small cages are particularly influential
factors. As described above, many of these abnormal
behaviors are resistant to change once they are established.
However, even though the link between these factors and
the development of abnormal behavior has been well
documented, some research facilities continue to manage
NHPs in ways that may induce the expression of abnormal
behavior. While these management practices
(e.g. individual housing) are often utilized to support the
biomedical research in which the animals participate,
everyone should be aware that these practices can and often
do cause behavioral problems. Reducing or eliminating the
use of these practices will help to significantly reduce the
expression of these behavioral problems in our laboratory
NHPs. For some facilities, these sorts of changes will
require a shift in philosophy and/or infrastructure within the
institution. Scientific investigators may need to be shown
