Biomedical Engineering Reference
In-Depth Information
contact the animal above or below resulting in finger injuries,
and sometimes animals in the lower cage may be contami-
nated from excrement from animals in the upper cages.
spontaneous adverse effects have been reported in
nonhuman primates through use of polycarbonate
drinking water bottles, the potential for adverse effects
associated with exposure to BPA should be considered
(
vomSaaletal.,2004
;
Erler and Novak, 2010; Newbold,
2010
). Polysulfone is a newer material that is also used to
manufacture animal drinking water bottles; although less
BPA may leach from polysulfone manufactured products
there is a risk of exposure to animals when this product is
used (
Howdeshell et al., 2003
).
Automatic watering systems deliver water to an “on
demand” stem-valve watering device usually located at the
back of the cage. The water device should be located where
animals can reach it easily even if they are unable to stand
or climb. Automatic water systems must be designed to
prevent back flow and to allow periodic system flushing and
chemical treatment of the watering system. The primary
advantage of automatic water systems is the cost savings
from reduced labor. Disadvantages are the potential system
failures and maintenance problems, inability to easily
determine if animals are drinking, and the potential for
disease transmission from animal to animal through the
water lines. These disadvantages largely can be overcome
through proper system design, installation, maintenance,
and monitoring.
Flush Pans
Flush pans can be added to wall-mounted or rack-mounted
cage systems. Flush pans must be sloped so that water flow
is directed toward a drain. Pans should be sloped front to
back rather than side to side. A side-to-side sloped pan
allows waste from one cage to flow underneath other cages
before reaching the drain. This may allow an animal to
reach down onto the pan and contact the waste from other
animals and increase the risk of disease transmission
(
Treuting et al., 1999
). A front-to-back slope reduces this
potential because waste flows a short distance to the back of
the pan and into a gutter and thus is inaccessible to animals.
Water flush pans are less labor intensive to clean than
individual removable pans. Waste pans can be flushed
frequently to reduce odors.
Automatic water flush systems for waste pans are not
commercially available and must be locally designed and
constructed. A flush system requires large volumes of
water being released at one time to provide adequate
flushing action. The sudden onset of the flushing can be
disturbing to primates, and certain types of enrichment,
including paper, are contraindicated because they may
clog drains.
Feeding and Foraging Devices
Food may be provided in food cups or bowls attached to the
cage. Typically, nonhuman primates will remove all the
food from the food container and drop it on the cage floor.
Some commercial diets are manufactured into large biscuit
shapes that prevent them from falling through the wire
floor. Some feeder boxes are too easily detached and
dropped by the primates, so look for ones that attach
securely, yet are removable for cleaning. Ensure that the
opening to the feeder is smooth, to avoid lacerations.
Various strategies have been developed to provide food
in ways to improve the psychological well-being of the
animals. Many of these strategies use devices that allow
animals to engage in foraging type behaviors (
Bloom and
Cook, 1989; Bayne et al., 1991; Lutz and Novak, 2005
).
Some devices are designed to accommodate regular
biscuits, so that animals must forage for their daily ration
(
Reinhardt, 1993, 1994; Murchison, 1995
). Other foraging
devices are puzzles provisioned with special treats like
peanuts or cereal that need to be extracted (
Crockett et al.,
2001
). Foraging boards are another variation (
Lutz and
Farrow, 1996
). The cage mesh spacing on the front of the
cage where the device is attached can negatively impact
foraging accessibility (
Sanders et al., 2008
), so select
devices appropriate for the caging. Some caging manu-
facturers advertise panels
Drinking Water Systems
Water may be provided to animals in individual cages in
bottles, bowls, or with an automatic watering system.
Water bowls are not recommended because of the
potential for spillage and contamination. Water bottles
may be economical for small numbers of animals but are
not practical when larger numbers of animals are main-
tained. Water bottles are labor intensive, requiring
frequent sanitization, reassembly, and refilling. When
water bottles are used, it is easy to determine if animals
are drinking or for monitoring fluid consumption which
may be necessary for certain veterinary therapy or
research applications. Bottles provide a route for
administration of medications, dietary supplements, and
test substances. Water restriction may be associated with
certain neuroscience (
National Research Council (Insti-
tute for Laboratory Animal Research), 2003
)orother
research protocols where only precise and limited quan-
tities of water may be provided. Most water bottles are
manufactured utilizing glass or polycarbonate. Poly-
carbonate water bottles are manufactured by polymer-
izing the chemical bisphenol A (BPA). Numerous studies
have shown effects from developmental as well as adult
exposure to BPA on a wide variety of traits in mollusks,
insects, fish,
for
swappable enrichment
frogs,
rats,
and mice. Although no
devices.
