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Guide for the Care and Use of Laboratory Animals{3948}Institutional Policies and Responsibilities Animal
environment, housing and management The online version (1996) is at http://www.nap.edu/readingroom/books/labrats. The "new Guide" (copyright 2010) is now available in pre-publication form:
The Guide applies to vertebrate animals used in testing,
teaching or research; it does not pertain to farm animals used in agricultural
settings, wildlife or aquatic animals in natural settings, or invertebrates. Institutional Policies and ResponsibilitiesOne of the "musts" of the Guide is that there must be
an IACUC (appointed by the responsible administrative official) to implement the recommendations of the Guide, oversee and evaluate
the animal care and use program. A second "must" is that a
veterinarian qualified through experience or training be associated with the
program. The IACUC inspects the facility every 6 months and sends a report to
the Institutional Official on the status of the animal care and use program as
well as other activities required by federal, state or local law. Animal care and use protocols should include discussion of a
number of topics, such as the rationale, species justification, alternatives,
personnel training, unusual housing and husbandry, appropriate
sedation/anesthesia/analgesia, unnecessary duplication, multiple surgeries,
criteria for intervention, postprocedural care, method of euthanasia and the
safety of the working environment for personnel. If a proposed procedure is so
new that there is no available information about its effect on the animals, the
IACUC should oversee limited pilot studies. Prolonged restraint should be avoided unless it is essential
for achieving the objectives of the research and is approved by the IACUC. It
should not be used solely for convenience, should be used for the minimum
period necessary with animals previously trained, and observation and
veterinary care should be provided for. Major surgery is defined as that which "penetrates and
exposes a body cavity or produces substantial impairment of physical or
physiologic function." Performance of multiple survival procedures on a
single animal is generally discouraged unless justified and approved by the
IACUC. Cost savings alone is not sufficient reason to perform multiple major
survival surgery. However, clinical reasons and scarcity of animal resources
may be acceptable reasons. Food or fluid restriction should be avoided, offering instead
items that are preferred as positive reinforcement. If restriction is
justified, some means of monitoring the animal’s well-being should be outlined,
such as monitoring of intake, weight changes, or state of hydration. People working with animals should be trained, and the
institution should provide on-the-job or formal training to help implement the
animal care and use program. Research workers should be qualified through
training or experience to perform anesthesia, surgery or other manipulations in
a humane manner. Another "must" of the Guide is that an occupational health and safety program be part of the animal care and use program. It must be consistent with federal, state and local regulations and focus on maintaining a safe and healthy workplace. Day-to-day responsibility rests with the PI, facility director or veterinarian. Hazard assessment is an important feature of the safety and health program, as are personnel training, personal hygiene, proper facilities, proper animal caging and other equipment, personal protective equipment, and a medical evaluation. Animal Environment, Housing
and Management
When designing new facilities, the recommendations in the Handbook
of Facilities Planning{4099} may be useful.
This book also contains information about many factors related to animal
husbandry (see facility
design and management).
A strategy for achieving the desired housing for animals should be developed by
animal care personnel and approved by the IACUC. After the decision-making
process, a means of objectively assessing the adequacy of the environment
should be used. The microenvironment of an animal is the primary enclosure with
its temperature, humidity, gas and particulate composition. The secondary
enclosure constitutes the macroenvironment. The microenvironment is often
different from the macroenvironment in temperature, humidity and gas
composition. Although the primary enclosure in general should be constructed of
durable materials that are easily disinfected, it is acceptable to use wood or
other less-durable materials for perches, climbing structures, resting areas
and perimeter fencing. Solid-bottom caging is recommended for rodents and
vinyl-coated flooring is often used for animals such as NHPs and dogs. Animals
maintained in outdoor enclosures must be protected from extremes
in temperature or other harsh weather, with adequate protective and escape
mechanisms for submissive animals. The issue of space for animals is one area in which the Guide may differ from Animal Welfare regulations, as the Guide recommends that basing cage size on floor space alone is inadequate. Indices such as health, reproduction, growth, behavior, activity and use of space can be used to assess the adequacy of housing. The minimum requirement is that the animal must have space to turn around and express normal postural adjustments, have ready access to food and water, and have enough clean-bedded or unobstructed area to move and rest in. Cats should have raised resting surfaces, and these may also be advisable for dogs and NHPs. Floor space occupied by appurtenances is not included in the space calculations. Temperature ranges are given below:
Generally, animals might be clinically affected if exposed to temperatures of <40° F or >85° F without a period of acclimation or access to shelter. Humidity should generally be between 30-70%. A rule of thumb of 10-15 air changes/hour has been used for years and is considered acceptable; however, a mechanical engineer should be consulted for more energy-saving and appropriate calculations. The American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) has published an average-total-heat-gain formula that can be used for animals. Recycled air (which should be HEPA-filtered) is not generally preferred unless it is returned to the room from which it came, is mixed with 50% fresh air, and is appropriately conditioned to address the thermal and humidity requirements of the animals in the room. Filters can be used to remove gaseous contaminants and odors, but these are expensive and difficult to monitor and maintain properly. Husbandry practices and limiting animal numbers within the secondary enclosure can be adjusted to fit the available air quality. Illumination should be sufficient for each species and allow good housekeeping, adequate visibility of the animals, and safe working conditions. Light ranges have only been developed for rats, which are nocturnal and albino. Light levels of 325 lux (30 ft-candles) at 1m from the floor are sufficient and do not cause phototoxicity in rats. For animals that have been shown to experience phototoxicity, light levels of 130-325 lux at the cage level should be provided. Management practices, such as provision of hiding places and rotating cages, can be used to reduce animals’ exposure to unwanted light levels. Noise levels of >85dB can
have deleterious effects on animals such as NHPs and rodents. Noisy animals
should be housed in environments that accommodate them, and away from quieter
animals. OSHA (1983 Hearing Conservation Amendment to the
Occupational Noise Exposure Standard) requires employers to administer a
continuing, effective hearing
conservation program for all employees whose noise exposures equal or exceed an
8-hour time-weighted average (TWA8) of 85 dbA.
(www.osha.gov/dts/osta/otm/noise/hcp/index.html)
Most diets that contain preservatives and are stored properly
can be used for up to about 6 months after manufacture. Vitamin C has a
shelf-life of only 3 months, so supplementation will be necessary if feed is
used beyond that time. Purified and chemically-defined diets are often less
stable than natural-ingredient diets, and so should be stored at 4°
C or lower and kept for less than 6 months. According to the EPA, hazardous wastes must be
rendered safe by sterilization, containment or other appropriate means before
removal from the facility. Animal identification means include many options, but toe-clipping
as a method of identifying small rodents should be used only when no other
method is feasible, and should be performed only on altricial neonates. ID
cards should contain the source of the animal, strain or stock, names and
locations of the PI, pertinent dates, and protocol number. Clinical records can
be valuable for dogs, cats, NHPs and farm animals. These should include
clinical and diagnostic information, date of inoculations, history of surgical
procedures and postop care and information on experimental use. Relevant
information should be provided when animals are transferred to another
institution. Sanitation of primary and secondary enclosures is covered by 9CFR and the Guide and are similar. One
slight difference is regarding the temperature of the water used for sanitizing
cages and equipment. 9CFR states that "hard surfaces of primary enclosures
and food and water receptacles must be sanitized using... hot water (at least
180° F) and soap or detergent, as with a mechanical
cage washer..." The Guide expands on this by saying that
"effective disinfection can be achieved with wash and rinse water at
143-180° F or
more.
The traditional 82.2°
C (180° F) temperature requirement for rinse water
refers to the water in the tank or in the sprayer manifold." Veterinary
Care
Adequate veterinary care includes programs in the following seven areas:
Duties of the veterinarian include providing guidance to
investigators and other personnel involved in the care and use of animals to
ensure appropriate handling, immobilization, sedation, analgesia, anesthesia
and euthanasia. The AV must provide guidance or oversight to
surgery programs and oversight of postop care. Animals must be procured lawfully, and dealers should
be inspected particularly in the case of USDA Class B dog and cat dealers.
Animals obtained from vendors should be evaluated for quality, i.e. by
analyzing health reports of genetic and pathogen status. Transportation should
minimize transit time, protect against environmental extremes, avoid
overcrowding, provide food and water when indicated and protect against
physical trauma. Regardless of the duration of quarantine after arrival, all
animals should be given a period for acclimation and stabilization before their
use. Transplantable tumors, hybridomas, cell lines and other materials can be
monitored by use of the mouse-antibody-production (MAP) test, the
rat-antibody-production (RAP) test, and the hamster-antibody-production (HAP)
test. An assessment of surgical outcomes should be performed to
ensure timely correction of problems and that appropriate procedures are being
followed. If the techniques are modified, outcome assessment should be even
more intense and might include more than just obvious morbidity or mortality. Elements of a surgical training plan include asepsis, gentle
tissue handling, minimal dissection, appropriate instrument use, effective
hemostasis and correct use of suture materials and patterns. It is the
responsibility of the IACUC to determine that people performing surgery are
qualified and trained. Non-survival surgery should entail the wearing of gloves,
clipping of the surgical site, and the use of clean instruments and surrounding
area. In general, non-rodent aseptic surgery should be conducted in
facilities intended for that purpose. Careful monitoring and timely attention
to problems increase the likelihood of success. The PI and the veterinarian share the responsibility for
ensuring that postop care is appropriate. In addition to providing for
temperature, cardiovascular and respiratory function, parenteral fluids,
analgesics or other drugs, incision care and record-keeping might be warranted. Fundamental to the relief of pain is the ability to recognize
it. Some species-specific manifestations include vocalization, depression,
abnormal appearance or posture, and immobility. Physical
Plant
Most of these recommendations are either common sense or were
covered in other places in the Guide. |
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©1999, Janet Becker Rodgers, DVM, MS, DipACLAM, MRCVS All rights reserved. Comments? Send an email to janet.rodgers@vet.ox.ac.uk |