Biomedical Engineering Reference
In-Depth Information
ventilated adequately with fresh, nonrecirculated air
because the animals tend to overcrowd into these areas.
Heated areas that are poorly ventilated may result in wet
floors, walls, and increased incidence of disease.
Indoor group housing facilities are comparatively costly
to build and maintain. Indoor/outdoor facilities may be
somewhat less costly to construct and operate than indoor
facilities; however, all animals must have access to the
environmentally controlled indoor portions of the facilities.
Outdoor facilities provide the most economical alternatives
for housing large groups in sizes and configurations
resembling those found in the natural state. Cage size
minimums apply, but generally group enclosures should be
considerably larger than the minimum to allow for
furnishings, running and climbing, social interactions, and
substrate maintenance. Depending on species' social
organization, the configuration of available space may be
more important than the actual size of the space in relation
to incidence of aggression, injuries, and disease (
Erwin and
Sackett, 1990
).
heat available, and must provide adequate ventilation
when required to protect primates from cold temperatures
(
US Department of Agriculture, 1991
). The sheltered
facility may be totally enclosed or the shelter may be an
indoor facility connected to an outdoor enclosure. An
outdoor housing facility is defined as any structure,
building, land, or premises intended to house animals in
which temperatures cannot be controlled within set
limits. Both sheltered and outdoor housing must provide
adequate protection from inclement weather. The shelter
must be of sufficient size to comfortably hold all
nonhuman primates in the facility at one time. There
must be multiple shelters or other means to ensure
protection of subordinate animals from aggressive or
dominant animals.
Enrichment
Group housing enclosures should include environmental
enrichment devices (also see Chapter 6). Various climbing
structures or jungle gyms provide animals with opportu-
nities to engage in species-typical behaviors such as
climbing and play while increasing the usable area of the
enclosure. Resting surfaces should allow animals to sit
above the ground surface in the sun or shade. Perches not
only provide structure but also allow animals to control
social interactions, and several perches may be necessary
to reduce competition for them (
Neveu and Deputte,
1996
). Climbing devices pose a risk of trauma when
animals jump or fall from high structures. Other envi-
ronmental enrichment structures, such as concrete culverts
and calf huts, provide hiding places and sight barriers to
reduce incidents of aggression and trauma (
Erwin et al.,
1976; Erwin, 1979
). Devices such as sticks, balls, and
plastic barrels also may help reduce fighting and
aggression.
Environmental enrichment furnishings may be natural
or artificial. Those made from natural materials such as
wooden logs or trees are realistic and economical but are
difficult to clean and may deteriorate rapidly. Natural
products must be removed and replaced periodically.
Artificial devices generally last longer, are usually repair-
able, can be sanitized, and allow for innovative design.
Artificial devices may cost more than natural devices.
Group enclosures should provide foraging opportunities
allowing primates to engage in species-typical behaviors.
This can be accomplished by using natural vegetation and
by scattering feed grains on the ground. Feed grains also
can be distributed in enclosures in deep bedding material
such as wood chips, sawdust, shredded paper, or straw
(
Chamove et al., 1982; Lutz and Novak, 1995
). Feeding
puzzles and other foraging devices can be placed strategi-
cally around the group enclosure to provide enrichment
(
Hayes, 1990; Lutz and Novak, 1995
).
Criteria for Selection of Facilities
Factors to consider when selecting indoor, indoor/outdoor,
or outdoor facilities for group housing nonhuman primates
include species, local climate, ventilation, environmental
enrichment, construction, food and water provision, pest
control, animal observation, animal handling, and security.
For additional discussion of group housing enclosure
design, see
Bohm and Kreitlein (2009)
.
Certain nonhuman primate species such as Macaca
nemestrina, Macaca fascicularis, and Chlorocebus
aethiops are less tolerant of cold weather than others and
cannot be housed outside in some geographical areas
without provisions for supplemental heat. The primate
species and their behavior patterns will affect the size and
strength of the enclosure. For example, brachiating species
require a large amount of vertical height and space to
swing. Arboreal species require more vertical space
whereas more terrestrial species require a combination of
climbing area for play and ground area for foraging. Adult
terrestrial species may require fewer climbing structures,
but young animals may benefit from these environmental
enhancement furnishings. The age of the animals may
determine if outdoor facilities are feasible during certain
times of the year. For example, infants and aged adults have
more difficulty adapting to sudden weather changes.
Federal regulations (
US Department of Agriculture,
1991
) require that large enclosuresdesignedtohouse
groups of animals must comply with minimal housing
requirements. A shelter is defined as a facility providing
the animals protection from inclement weather and
temperature extremes at all times. The sheltered portion
of the enclosure must provide adequate light, must have
