The Development of Science-based Guidelines for Laboratory Animal Care Proceedings of the November 2003 International Workshop (2004) / Chapter Skim
Currently Skimming:
Session 4: Environmental Control for Animal Housing
Session 4: Environmental Control for Animal Housing
Pages 131-166
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 131... ...
Session 4 Environmental Control for Animal Housing
|
From page 133... ...
The most widely accepted publication and the primary reference on animal care and use is the Guide for the Care and Use of Laboratory Animals (the Guide) , published by the National Research Council (NRC 1996)
|
From page 134... ...
recommendation from the Guide. This range has proven to be a good range although different approaches allow lower ventilation rates while maintaining a stable animal room environment (i.e., ventilated caging systems)
|
From page 135... ...
Containment Reduction of cross-contamination between holding rooms is normally accomplished through pressurization -- supply/exhausting air to/from the room to direct air in or out of the room. Quarantine, isolation, biohazards, and nonhuman primates should be kept under negative pressure.
|
From page 136... ...
The method is further evolving to include fresh air dwell times, particulate movement, stagnation, and projected odor levels. Other parameters that may be studied include inlet diffuser type, animal heat loads, cage/rack placement, and exhaust air systems placement.
|
From page 137... ...
FIGURE 3 Examples of differences among the hearing ranges of humans and various animal species. Modified from Warfield (1973)
|
From page 138... ...
Performance Standard for Ventilated Cages Ventilated caging systems have evolved into many different airflow strategies based on the work of various manufacturers. Generally, manufacturers have worked closely with animal research professionals to develop caging systems that have well-founded concepts.
|
From page 139... ...
Vol 2. Laboratory Animal Facilities.
|
From page 140... ...
The aim of international regulations for the care and use of laboratory animals is to enhance animal welfare, to set standards, to harmonize procedures, and to safeguard the quality of biomedical research.
|
From page 141... ...
Thus, where science could not support the discussions during the Working Party meetings, there was no other option than to rely on expert views and common sense -- a procedure that is fully justifiable but that emphasizes at the same time the need for further research into the tuning of housing conditions in the laboratory with the needs of the animals living in this artificial environment. The main problem to be solved is to generate
|
From page 142... ...
Furthermore, the classical approach of looking for signs of distress and/or discomfort evoked by imperfect housing conditions could be supplemented by studying expressions of pleasant experience. Predictability and controllability of the environment can be very rewarding to the animals and may therefore be expected to contribute to the well-being of captive living animals.
|
From page 143... ...
than 45% particular very · Provide sensitive to opportunity ultrasound to control · Ultrasound microclimate may affect prenatal development · Sudden loud noises may cause audiogenic seizures Dogs · 15-21ºC · Control · Duration · Noise in dog when precise unnecessary of the light kennels can control is · Can be period reach high required exposed to should be levels that can during wide at least cause damage procedures fluctuations 10-12 hr to humans and · Otherwise a of ambient · Low-level that could wider range relative night affect the provided that humidity lighting dogs' health welfare is not without (5-10 lux) and compromised adverse should be physiology effects provided · By addressing to avoid the dogs' startle reflex behavioral needs, barking may be decreased continued
|
From page 144... ...
144 SCIENCE-BASED GUIDELINES FOR LABORATORY ANIMAL CARE TABLE 2 Continued Temperature Humidity Lighting Noise Cats · 15-21ºC · Control · Duration · Unpredictable when precise unnecessary of the light noise may control is · Can be period cause stress required exposed to should be during wide at least procedures fluctuations 10-12 hr · Otherwise a of ambient · Low-level wider range relative night provided that humidity lighting welfare is not without (5-10 lux) compromised adverse should be effects provided to avoid startle reflex · Light sources may be perceived as flickering because of the cats' high critical fusion frequency Ferrets · 15-24ºC · Control · Duration · Lack of sound · Absence of unnecessary of the light or auditory well- · Can be period stimulation developed exposed to may vary can be sweat glands wide between detrimental may lead to fluctuations 8-16 hr and make risk of heat of ambient · Modification ferrets nervous exhaustion relative of the · Loud when exposed humidity photoperiod unfamiliar to high without is an noise and temperatures adverse important vibration have effects tool for the been reported manipulation to cause of the stress-related reproductive disorders cycle continued
|
From page 145... ...
ENVIRONMENTAL CONTROL FOR ANIMAL HOUSING 145 TABLE 2 Continued Temperature Humidity Lighting Noise Nonhuman Primates · Marmosets and Tamarins · 23-28ºC · 40-70% but · Not less · Exposure to but slightly levels higher than 12 hr ultrasound higher than 70% of light should be levels are will be · Provision minimized acceptable tolerated of a shaded area · Squirrel Monkeys · 23-28ºC · 40-70% · Not less without than 8 hr abrupt of light temperature · Light variations spectrum should resemble daylight, i.e. including UV light · Macaques and Vervets · 16-25ºC is · 40-70% · 12:12 suitable light/dark · 21-28ºC is cycle more suitable for long-tailed macaques · Baboons · 16-28ºC is suitable continued
|
From page 146... ...
146 SCIENCE-BASED GUIDELINES FOR LABORATORY ANIMAL CARE TABLE 2 Continued Temperature Humidity Lighting Noise Amphibians · Amphibians · A hydrated · Photo- · Noise, are integument periods vibration, ectothermic and the and light and · Areas of possibility intensities unexpected different to take up should be stimuli temperatures moisture consistent should be are beneficial through the with the minimized · Exposure to skin are natural frequent essential conditions fluctuations in temperature should be avoided · Aquatic · 15-22ºC · 100% urodeles · Aquatic · 18-20ºC · 100% anurans · Semi- · 8-10ºC · 50-80% aquatic anurans · Semi- · 23-27ºC · 80% terrestrial anurans · Arboreal · 18-25ºC · 50-70% anurans NOTE: For ventilation the provisions in the General Part apply to all species. The same applies for empty cells in the table.
|
From page 147... ...
In addition, scientific design and replication of studies varies: One poorly designed study can dictate standards inappropriately. The moderator posited that the influences on standards, other than peer-reviewed scientific data, include daily practice, common sense, and prevailing expert views.
|
From page 148... ...
The safety and efficiency of people working in the room have been studied more than the preceding category, but often in studies unrelated to laboratory animal care. Human effectiveness and its variability under different lighting conditions are relatively well studied.
|
From page 149... ...
It is hoped that online publishing will help resolve this problem, but participants recognize that a strong demand for complete disclosure of husbandry, including light management, is needed.
|
From page 150... ...
Because 50 Hz is used as the typical cycle for power in Europe, fluorescent bulbs flicker at 50 Hz, rather than at 60 Hz, the cycle commonly used in the United States. The critical fusion frequency for an individual or species is the frequency at which a cycling light would be perceived as a continuous light source.
|
From page 151... ...
It is common for engineering standards to conflict with performance standards. EFFECT OF CURRENT REGULATIONS ON THE WELFARE OF THE ANIMALS "Shoulds" tend to evolve into "musts." There is a strong need for the use of adaptive management in many laboratory animal maintenance situations.
|
From page 152... ...
It is possible for IACUC chairs to prefer strong and narrow regulations with tight interpretations to facilitate their ability to exert control over investigators who are not in optimal compliance. That approach, of functioning as a policeman and an enforcer, is one alternative; however, the approach of working with investigators as part of a team to improve animal welfare and care seems to be more effective.
|
From page 153... ...
Sherri Motzel, Director of Laboratory Animal Resources at Merck Research Laboratories, presented a scholarly review of the effects of noise, vibration, and sound. The review included definitions, the current regulations and standards for noise, reviews of several relevant studies for rodents and nonhuman primates, and opportunities for noise, sound, and vibration mitigation.
|
From page 154... ...
This study and other reports in the literature indicate that much more emphasis should be placed on monitoring and controlling noise levels at multiple frequency and intensity ranges outside human hearing ranges in animal facilities because of the potential for adverse effects on study data and outcomes. Preventive maintenance and facility testing, facility design, and work practices should also be reassessed in the laboratory animal facility in an effort to mitigate adverse noise effects.
|
From page 155... ...
Additional in-depth review of the literature combined with relevant research studies to address noise effects in laboratory animals is clearly indicated. Participants agreed that current regulations and guidelines should be revised and updated accordingly.
|
From page 156... ...
Barthold The introductory discussion focused on the impact of new guidelines on immune response and metabolism. Significant changes that may influence these responses include social grouping, environmental enrichment, and enclosure size.
|
From page 157... ...
. · Single housing of African green monkeys induces immunosuppression (Suleman and others 1999)
|
From page 158... ...
. Examples of situations involving laboratory rodents include the following: · Single housing does not change glucocorticoid concentrations (Benton and Brain 1981; Misslin and others 1982)
|
From page 159... ...
Dr. Nevalainen presented data regarding volatile compounds in bedding, and environmental enrichment with variable material.
|
From page 160... ...
Many participants indicated that guidelines and regulations are not the answer. The Materials and Methods sections in scientific publications must provide documentation of the study design, including such variables.
|
From page 161... ...
1992. Removal from natal social group to peer housing affects cortisol levels and abso lute numbers of T cell subsets in juvenile rhesus monkeys.
|
From page 162... ...
1997. Effects of social housing condition on the response of the Shionogi mouse mammary carcinoma (SC115)
|
From page 163... ...
Influence of change from grouped to individual housing on a T-cell-dependent immune response in mice: antagonism by diazepam. Pharmacol Biochem Behav 47:497-502.
|
From page 164... ...
3 and BSL4 housing for agricultural animals and nonhuman primates. The impetus for this discussion is the new funding for facility construction for national and regional containment laboratories and other research programs.
|
From page 165... ...
One particular gap identified by participants was how to determine cooling load in a room with ventilated caging systems, that is, how much of the load is removed from the room by the exhaust and how much heat is transferred to the room from the cage. Data are needed in this area.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.