Recognition and Alleviation of Pain
Refinement of Handling and Housing Conditions (Enrichment)
Species-Specific Requirements for Enrichment


"Techniques that improve upon the accuracy of measurements and reduce or eliminate sources of variability have the potential for reducing the number of animals required in a given protocol." Brockway B, Hassler C and Hicks N.
"The standards ... shall, with respect to animals in research facilities, include requirements-- (A) for animal care, treatment, and practices in experimental procedures to ensure that animal pain and distress are minimized, including adequate veterinary care with the appropriate use of anesthetic, analgesic or tranquilizing drugs, or euthanasia." AWA Section 13 (a)(3).


"Advancing refinement of laboratory animal use." Smaje LH. 1998. Laboratory Animals 32 (2), 137-142.
Various aspects of refinement are described and a series of practical recommendations for advancing refinement of laboratory animal use are given.
Altweb special section on Refinement. 2009
This refinement section begins with introductory text explaining the topic in non-technical language, accompanied by a set of links to relevant databases, web sites, books, articles, abstracts, and so on. The section addresses the following topics: What is pain and distress? Definitions, biology and physiology; Recognition and assessment of pain and distress; Alleviation and prevention of pain in animals; Humane endpoints; Euthanasia; Enrichment.
"Animal definition: a necessity for the validity of animal experiments?" Öbrink KJ and Rehbinder C. 1999. Laboratory Animals 22, 121-130.
"In most scientific journals, experimental animals are described poorly... The animal definition should not only include species, sex and age but also ... the environmental conditions to which the animals are exposed. ... The prerequisites for the use of fewer animals per project, while still retaining a sufficiently high degree of accuracy are high levels of reproducibility and precision in the experimental results. Factors that may affect these will be discussed in this paper. If a researcher, through carelessness or ignorance, should use more animals for a project than is necessary, it must be considered unethical."
"Ethology recommendations for a standardized minimum description of animal treatment." Davis DE, Bennett CL, Berkson G, Lang CM, Snyder RL and Pick JR, ILAR Committee on Laboratory Animals. 1973. ILAR [Institute for Laboratory Animal Research] News/Journal 16(4), 3-4.
"It is clear [from this survey] that many investigators do not realize the influence of ... environmental variables [e.g., housing, handling, temperature, light] on experimental results or at least do not adequately describe the environmental history of the animals used for experimentation."
"Importance of non-statistical design in refining animal experiments." Morton D. 1998. Australian and New Zealand Council for the Care of Animals in Research and Teaching (ANZCCART) News 11(2), insert: 1-12. An ANZCCART News Fact Sheet.
Detailed discussion of approaches to refinement, including good animal care, use of anaesthetics and analgesics, humane end points; suggestions of strategies that can contribute markedly to minimising pain and suffering in an experiment and reduce animal numbers; extensive bibliography. Refinement can be defined as: "Those methods which avoid, alleviate or minimise the potential pain, distress or other adverse effects suffered by the animals involved, or which enhance animal wellbeing If scientists wish to claim they practise humane science then they have to pay as much attention to avoiding unnecessary pain and distress to their animals as they do to their scientific objectives. Factors leading to good animal welfare will usually also lead to reliable, accurate and economic science."
"The influences of standard laboratory cages on rodents and the validity of research data." Sherwin CM. 2004. Science in the Service of Animal Welfare. Kirkwood JK, Roberts EA and Vickery S, eds. Proceedings of the UFAW International Symposium, Edinburgh, 2-4 April 2003. Animal Welfare 13: S9-15.
This paper reviews various influences of standard laboratory cage design and husbandry... These studies show that the development and responses of animals from standard laboratory housing and husbandry conditions are often unrepresentative and idiosyncratic, indicating that data are likely to have reduced external validity. .. Standard laboratory housing may sometimes be associated both with reduced welfare and with reduced benefits gained from research.
"Minimizing stress during physiological monitoring." Brockway BP, Hassler CR and Hicks N. 1993. Refinement and Reduction in Animal Testing. Niemi SM and Willson JE , eds, 56-69. Proceedings of a conference held by the Scientists Center for Animal Welfare.
"Minimizing or eliminating extraneous stress factors from the experimental design is crucial to a true understanding of the compound, device or technique being evaluated for its effects. Furthermore, it follows that the elimination of sources of variability (stress, for example) may allow the use of fewer animals giving equally valid results." Alternatives to traditional methods of monitoring laboratory animals are suggested.
"Refinement and reduction through the control of variation." Festing MFW. 2004. In: The Three Rs at the Beginning of the 21st Century: Proceedings of the Fourth World Congress on Alternatives and Animal Use in the Life Sciences, 11-15 August 2002, New Orleans, LA, USA. Balls M, Firmani D and Rowan A, eds. 2004. ATLA 32, Supplement 1, 259-263.
"The key to doing animal experiments efficiently, while using the minimum number of animals without loss of scientific information, lies in good control of random variation, and recognition and control of “fixed effect” variation, such as the sex or strain of the animals."
"Stereotypies and other abnormal repetitive behaviors: Potential impact on validity, reliability, and replicability of scientific outcomes." Garner JP. 2005. ILAR Journal Vol 46(2).
"Captive environments may affect the following aspects of an experiment: validity, by introducing abnormal animals into experiments; reliability, by increasing interindividual variation through the introduction of such individuals; and replicability, by altering the number and type of such individuals between laboratories. Thus, far from increasing variability, enrichment may actually improve validity, reliability, and replicability by reducing the number of abnormal animals introduced into experiments. In this article, the specific example of abnormal repetitive behaviors (ARBs) is explored... ARBs in laboratory animals may compromise validity, reliability, and replicability, especially in behavioral experiments; and enrichments that prevent ARB may enhance validity, reliability, and replicability."
"Using Fewer Research Animals." Chamove AS. 2003. Laboratory Primate Newsletter 42(1), 1-2.
Sequential sampling and power analysis are more ethical alternatives to reduce animal numbers to the lowest number possible, especially when test procedures are aversive.
"Variables in animal based research: Part 2. Variability associated with experimental conditions and techniques." Reilly J 1998. Australian and New Zealand Council for the Care of Animals in Research and Teaching (ANZCCART) News 11(1), insert: 1-12. An ANZCCART News Fact Sheet.
This Facts Sheet addresses the issues of variability associated with experimental conditions and techniques and includes the effects of stress, sampling techniques, anaesthesia and euthanasia, and how these may affect research data. "These variables should be defined, standardised, and minimised in order to obtain results which are meaningful, repeatable, and comparable with others... Refinement of research techniques using animals will lead to less animal distress and at the same time will usually lead to higher quality and more robust data."
Variables, Refinement and Environmental Enrichment for Rodents and Rabbits kept in Research Institutions. Making Life Easier for Animals in Laboratories. Reinhardt V and Reinhardt A. 2006. Animal Welfare Institute. Washington, DC. Available from Animal Welfare Institute, PO Box 3650, Washington, DC 20007.
This book summarizes and discusses refinement and environmental improvement techniques for rodents and rabbits kept in research facilities. The review of the literature focuses on data-supported published material and mentions descriptive and theoretical articles only if they have practical relevance. A total of 260 relevant articles published in 85 different journals have been reviewed.

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Recognition and Alleviation of Pain

"AVMA Guidelines on Euthanasia." 2007.
Useful reference to insure that appropriate methods of euthanasia are being used for different laboratory animal species.
"Adverse effects in animals and their relevance to refining scientific procedures." Morton DB. 1990. ATLA (Alternatives to Laboratory Animals) 18, 29-39.
The author highlights areas in which suffering can be prevented, alleviated and avoided. The terms "pain, stress, eustress, distress and fear" are clearly defined to help determine animal suffering. "One has to recognize suffering by non-verbal means, i.e., through observing changes in behavior patterns and in physiology."
"Assessment and alleviation of post-operative pain." Flecknell P. 1997/98. Animal Welfare Information Center Newsletter 8(3-4) 8-14.
The author addresses a few common concerns about the use of analgesics to relieve post-operative pain, describes various methods of pain assessment such as scoring systems, gives suggestions on the clinical use of analgesics and offers recommendations on the relief of post-operative distress. Tables with recommended dosages of analgesics are given. "Providing effective post-operative pain relief can have a dramatic effect on the speed with which animals return to normality following surgical procedures. The provision of good post-operative care should be considered essential both because of a concern for the animal's welfare and also because it is good scientific practice."
*Assessing the Health and Welfare of Laboratory Animals. Web site. University of Newcastle. 2008. Supported by the 3R Research Foundation Switzerland.
Tutorials and resources for guidance in recognizing signs of health and good welfare and identifying signs of pain, distress and poor welfare in laboratory animals.
Guidance Document on the Recognition, Assessment, and Use of Clinical Signs as Humane Endpoints for Experimental Animals Used in Safety Evaluation. 2000. Organisation for Economic Cooperation and Development (OECD). Paris, France.
The purpose of the document is to apply the principles of the Three Rs to the use of animals in regulatory toxicity tests. It specifically addresses refinement and describes approaches to detecting clinical signs of pain and distress and procedures that can be put in place to minimise test animal pain, distress, and suffering during testing.
"Guidelines on the recognition of pain, distress and discomfort in experimental animals and an hypothesis for assessment." Morton DB and Griffiths PHM. 1985. Veterinary Record 116, 431-436.
The article helps not only newcomers inexperienced in the recognition of pain, but also experienced workers who may be called upon to evaluate the pain involved in a new model or an individual animal. Specific signs of behavior and common clinical signs indicating pain, distress or discomfort in laboratory animals are listed and discussed.
Guidelines on Choosing an Appropriate Endpoint in Experiments Using Animals for Research, Education, and Testing. 1999. Canadian Council on Animal Care. Ottawa, Ontario.
Guidelines are presented for selecting an endpoint that reduces animal pain and/or distress. "For the purposes of these guidelines, the term 'Endpoint' is defined as the point at which an experimental animal's pain and/or distress is terminated, minimized or reduced, by taking actions such as killing the animal humanely, terminating a painful procedure, or giving treatment to relieve pain and/or distress."
Humane Endpoints in Animal Experiments for Biomedical Research. Hendriksen FM, Morton DB, eds. 1998. Proceedings of the International Conference, 22-25 November 1998, Zeist, The Netherlands. Laboratory Animals Ltd. London, England.
The papers presented address issues relating to the recognition and assessment of adverse effects in animals, and the determination, validation, implementation and acceptance of humane endpoints.
"Implementing assessment techniques for pain management and humane endpoints." Morton DB. 1998. Pain Management and Humane Endpoints. Proceedings of a workshop. Johns Hopkins Center for Alternatives to Animal Testing (CAAT).
Score sheets are drawn up for each scientific procedure, and for each species, listing cardinal clinical signs that are observable and measurable, developed through the experience of a team of observers. The score sheet system helps focus attention on an animal's condition throughout the procedure. It also helps determine the effectiveness of any therapy intended to relieve adverse effects, and which experimental models cause the least pain and distress, thus helping to refine scientific procedures. This technique is especially useful with new procedures, or when users are not sure of what effects a procedure will have.
"Invasiveness scales for animal pain and distress." Orlans FB. 1996. Lab Animal 25(6), 23-25.
Recommends the use of well-defined invasiveness scales to improve animal welfare standards. By using such scales "laboratory workers would acquire greater sensitivity to animal pain and distress, improving ethical decision making."
"Pain–assessment, alleviation and avoidance in laboratory animals." Flecknell P. 1999. An ANZCCART factsheet. Australian and New Zealand Council for the Care of Animals in Research and Teaching (ANZCCART) News 12 (4), insert 1-10.
Valuable suggestions are given for the recognition of pain in laboratory animals and facilitation of its assessment. Available methods of pain control and their implementation are outlined. Control of acute pain can be achieved relatively easily in most mammalian species by use of analgesics agents. It is important to consider not only measures directed towards alleviating or preventing pain, but also the overall care of the animal and the prevention of distress. Tables with analgesic dosages for ferrets, guinea pigs, mice, rats, rabbits, cats, dogs, pigs, sheep and non-human primates are included.
"Pain and distress: what really matters?" Koch VW 2006. Lab Animal 35(5) 27-32.
"The author argues that IACUCs and investigators should shift their focus from the word 'pain' to the more inclusive word 'distress' referring to any mentally unpleasant level of stress in an animal, including slight discomfort. She discusses criteria for defining 'significant' distress, and offers suggestions for the conduct of studies to determine levels of distress."
Pain Management and Humane Endpoints. Johns Hopkins Center for Alternatives to Animal Testing. 1998. Proceedings of a workshop.
Excellent papers on assessment and alleviation of pain and distress, policy, implementation and humane endpoints. Useful information for IACUCs on how to review protocols and potentially painful procedures, and on their responsibilities in the implementation of policy leading to avoidance and minimization of pain in animals.
"Physiological and ethological aspects of the assessment of pain, distress and suffering." Scharmann W. 1998. Humane Endpoints in Animal Experiments for Biomedical Research. Hendriksen FM, Morton DB, eds. Proceedings of the International Conference, 22-25 November 1998, Zeist, The Netherlands. 33-39. Laboratory Animals Ltd. London, England.
Practical approaches to the recognition of pain and grading of pain intensity are described.
"Practical applications of animal harm scales: international perspectives." Orlans, FB. 2000. In Progress in the Reduction, Refinement and Replacement of Animal Experimentation. Balls E, van Zeller AM and Halder ME, eds. 1049-1056. Elsevier. Amsterdam, Netherlands.
Harm scales have been introduced in several countries to categorise degrees of animal pain or distress resulting from experimental procedures. These scales serve three purposes: 1. They promote an understanding of fundamental concepts of humane animal experimentation, the three Rs, and sensitise investigators and reviewers to the ethical significance of animal harm. 2. Harm scales are useful in framing policies on the use of animals in education. 3. In the reporting of national statistics on laboratory animal use, increased public accountability occurs if data are reported according to level of harm.
Recognition and Alleviation of Pain and Distress in Laboratory Animals. Committee on Pain and Distress in Laboratory Animals, Institute for Laboratory Animals Research, National Research Council. 2008. National Academy Press. Washington, DC.
An introduction to the basis, recognition and assessment of pain, stress and distress. Discusses the pharmacology of general anesthesia; describes major classes of drugs used to achieve the clinical goals of analgesia, sedation and immobilization and lists doses per animal species; summarizes and supplements the Report of the American Veterinary Medical Association Panel on Euthanasia with emphasis on animals used in research, testing and teaching.
"Recognizing animal suffering and pain." Mroczek NS. 1994. Lab Animal 23(1), 27-31.
"Recognizing pain in animals requires empathic observation, which in turn engenders identification and often sympathy. Scientists have undertaken voluminous research which is based on the assumption that animals do feel pain. Pain inherent in animal research, however, is often ignored as subjective experience of the animal's reality in a simplistic attempt to objectify animal life and hence reduce it to measurable data."
"Post-operative care and analgesia of farm animals used in biomedical research.[scroll down]" Randolph MM. 1994. Animal Welfare Information Center 5(1), 11-13.
Excellent guidance for the post-operative care and analgesia of farm animals used in research. "An astute caretaker's knowledge of the normal behavior for that particular age, sex, species, and individual is crucial in determining when animals are experiencing unacceptable levels of pain. ... The recovery period should be viewed as the final stage in the surgical procedure. Some investigators and their staff have underestimated the importance of this stage of the surgical endeavor. There can be no successful surgery with an unsuccessful recovery." This article includes a clear table with practical, post-operative analgesics for ruminants and pigs.
Research Animal Anesthesia, Analgesia and Surgery. Smith AC and Swindle MM , eds. 1994. Scientists Center for Animal Welfare. Greenbelt, MD.
A conference report with excellent contributions on "Intraoperative monitoring and equipment" Hoyt RF, 137-146; "Cardiopulmonary complications and emergencies in surgery" Swearengen JR, 159-166; "Rabbits and rodents: Anesthesia and analgesia" Wixson SK, 59-92; "Dogs and cats: Anesthesia and analgesia" Daunt DA, 93-105; "Miscellaneous species: Anesthesia and analgesia" Schaeffer DO, 129-136.
"Stress and distress." Roberts SA et al. 2006. Animal Technology and Welfare, 5, 99-102
Definitions and practical hints on how to recognize stress and distress.

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Refinement of Handling and Housing Conditions (Enrichment)

"Proper housing and management of animal facilities are essential to animal well-being, to the quality of research data and teaching or testing programs in which animals are used, and to the health and safety of personnel. A good management program provides the environment, housing, and care that permit animals to grow, mature, reproduce, and maintain good health; provides for their well-being; and minimizes variations that can affect research results."                                                Guide for the Care and Use of Laboratory Animals

"Behavioral indexes of poor welfare in laboratory rats." Patterson-Kane EG, Hunt M and Harper DN. 1999. Journal of Applied Animal Welfare 2, 97-110.
Fearfulness associated with single-housing was alleviated by pair-housing, and even further alleviated by group-housing in enriched cages. Problem solving ability was improved when rats were kept in groups in enriched cages rather than in barren single cages.
"Cage enrichment for hamsters housed in suspended wire cages." McClure DE and Thomson JI. 1992. Contemporary Topics in Laboratory Animal Science 31(4), 33.
"When these hamsters were provided with nesting material their well-being was improved as indicated by resolution of inappetence and depression. Providing the PVC apparently resolved the aggressive behavior problem by providing a means for seclusion in addition to functioning as a burrow and as a toy."
"Catching individual rhesus monkeys living in captive groups." Reinhardt V. 1990. Available from Wisconsin Regional Primate Research Center, 1220 Capitol Court, Madison, WI 53715.
This 17-minute videotape demonstrates how rhesus macaques living in a breeding troop can readily be trained to enter a chute voluntarily or on vocal command and exit one-by-one into a transport box to allow capture. The procedure avoids undue stress; it is carried out by a single person.
Comfortable Quarters for Laboratory Animals. Reinhardt V and Reinhardt A. eds. 2002. 9th edition, Animal Welfare Institute. Washington, DC. Available from Animal Welfare Institute, PO Box 3650, Washington, DC 20007.
A collection of 16 articles outlining refined, i.e., species-appropriate housing conditions and handling techniques for mice, gerbils, rats, hamsters, guinea pigs, rabbits, cats, dogs, primates, pigs, sheep, cattle, horses, chickens, amphibians and reptiles. Suggestions and recommendations are made which minimize or eliminate variables such as distress, fear, anxiety, discomfort, depression and boredom "thereby maximizing the research animals' well-being and reducing the number of subjects required to achieve statistical significance of the research data."
"The effect of feeding and housing on the behaviour of the laboratory rabbit." Krohn TC, Ritskes-Hoitinga J and Svendsen P. 1999. Laboratory Animals 33, 101-107.
"While the [individually housed] rabbits in cages spent 2-5% of the time performing abnormal behaviour like biting the bars or scratching the bottom of the cage, these activities were virtually absent in group-housed rabbits in floor pens."
"Effects of environmental enrichment on behaviour and reproductivity of growing pigs." Beattie VW, Walker N and Sneddon IA. 1995. Animal Welfare 4, 207-220.
"Enriching the environment [extra area with peat and a straw hopper; four times as much floor space] reduced both the amount of time pigs spent inactive and the time involved in harmful social and aggressive behaviour. Tail biting was absent from the enriched environment but four pigs were removed from barren pens with severe tail damage."
"An enrichment object that reduces aggressiveness and mortality in caged laying hens." Gvaryahu G, Ararat E, Asaf E, Lev M, Weller JI, Robinzon B and Snapir N. 1994. Psychology and Behavior 55, 313-316.
"The enrichment devices (colored key rings) significantly reduced aggressive head-pecking behavior and significantly decreased the mortality rate."
Enrichment Strategies for Laboratory Animals. (whole issue). 2005. ILAR Journal Volume 46(2).
"Currently, it is recognized that science also has an ethical responsibility to house animals according to their species-specific needs, and that responsibility invokes the concept of behavioral and environmental enrichment.... To develop enrichment programs and to assess the effectiveness of such programs, it is critically important for all staff members involved in the care and use of the animals to understand the behaviors of the individual species that are housed."
"Environmental enrichment of laboratory animals used in regulatory toxicology studies." Dean SW. 1999. Laboratory Animals 33, 309-327.
"A creative approach to environmental enrichment is indeed compatible with regulatory toxicology. It is hoped that this will encourage those responsible for the care and welfare of animals in such a laboratory to challenge historical practices and include environmental enrichment as a fundamental necessity of study design... The assumption that certain regulatory authorities 'prefer' single-housing should be challenged... Group housing should become the norm whenever animals are compatible, and anything less should be justified on the basis of sound science."
Guide to the Care and Use of Experimental Animals, Vol. 2, Gilman J , ed. 1984. Canadian Council on Animal Care. Ottawa, Ontario.
Excellent guidelines for the species-appropriate keeping of amphibians, reptiles, and pigeons in the research laboratory setting; in the process of being updated. Chapters can still be accessed individually: amphibians; reptiles, pigeons & doves; etc.
*Guidelines on: the care and use of farm animals in research, teaching and testing. Tennessen T. et al. 2009. Canadian Council on Animal Care. Ottawa, Ontario.
Provides information for investigators, animal care committees, facility managers and animal care staff that will assist in improving both the care given to farm animals and the manner in which experimental procedures are carried out. The refinement of animal care and use guidelines is a continuous process. These guidelines are intended primarily to provide assistance in the implementation of best practices. They apply to farm animals used by institutions for scientific purposes. under which animals should be cared for and maintained.
Guidelines on: The Care and Use of Fish in Research, Teaching and Testing. Chris Harvey-Clark et al. 2005. Canadian Council on Animal Care. Ottawa, Ontario.
These guidelines aim to provide information for investigators, animal care committees, facility managers and animal care staff that will assist in improving both the care given to fishes and the manner in which experimental procedures are carried out.
Making Lives Easier for Animals in Research Labs: Discussions by the Laboratory Animal Refinement & Enrichment Forum. Baumans V et al. (eds) 2007. Animal Welfare Institute. Washington, DC. Available from Animal Welfare Institute, PO Box 3650, Washington, DC 20007.
This book is a collection of electronic discussions that took place on the Laboratory Animal Refinement & Enrichment Forum (LAREF) between October 2002 and May 2007. The forum serves the international animal care and animal research community to promote animal welfare and improve scientific methodology by avoiding or minimizing stress and distress resulting from husbandry and handling practices.
Of more than 5,000 comments posted, approximately 3,000 were selected for this book because they have practical animal welfare relevance and are based on first-hand experiences about ways to improve the conditions under which animals are housed and handled in research facilities.
The following main topics are discussed: Basic Issues; Maladaptive Behaviors; Environmental Enrichment; Social Housing; Working With Animals; Extraneous Variables.
"Pair-housing overcomes self-biting behavior in macaques." Reinhardt V. 1999. Laboratory Primate Newsletter 38(1), 4.
"The transfer to a compatible social-housing arrangement [isosexual pair-housing] effectively cured the [seven] rhesus subjects from the behavioral pathology of habitual self-biting."
"Restraint methods of laboratory nonhuman primates: A critical review." Reinhardt V, Liss C and Stevens C. 1995. Animal Welfare 4, 221-238.
Nonhuman primates can readily be trained to co-operate rather than resist during common handling procedures, thereby avoiding data-biasing distress responses associated with traditional involuntary restraint techniques.
"The role of husbandry in promoting the welfare of laboratory animals." Reese EP. 1991. Animals in Biomedical Research, Hendriksen CFM and Koëter HBWM , eds, 155-192. Elsevier. Amsterdam, Netherlands.
A very well written outline of refinement options to promote the welfare of laboratory animals. "It appears that many of our laboratory findings are based upon data from distressed animals."
"Social housing ameliorates behavioral pathology in Cebus apella." Bayne K, Dexter SL and Suomi SJ. 1991. Laboratory Primate Newsletter 30(2), 9-12.
Change from single- to group-housing "effectively reduced stereotypic behavior s; however, it also was associated with more passive behaviors being exhibited by the subjects. The concurrent shifts in these components of the behavioral repertoire suggests that the animals were in a calmer state when housed socially."
*Taking Better Care of Monkeys and Apes: : Refinement of Housing and Handling Practices for Caged Nonhuman Primates. Reinhardt V. 2008.
Reviews the literature on the refinement of traditional housing and handling practices for nonhuman primates who live in cages alone, in pairs or trios. housing and handling practices of caged nonhuman primates can be refined, without undue labor and expenses, in such a way that distress responses are minimized or avoided if basic ethological principles are applied: (1) address the animal’s need to be with and interact with at least one compatible conspecific; (2) structure their living quarters in species-appropriate ways; (3) address their biologically strong motivation to forage; (4) train them to cooperate during procedures.“
"Use of cornhusk nesting material to reduce aggression in caged mice." Armstrong KR, Clark TR and Peterson MR. 1998. Contemporary Topics in Laboratory Animal Science 37(4), 64-66.
The provision of cornhusk reduced aggressive interactions by offering subordinate animals cover and escape routes.

See also:
Database on Refinement of Housing and Handling Conditions and Environmental Enrichment for Laboratory Animals: Rodents, Rabbits, Cats, Dogs, Ferrets, Farm Animals, Horses, Birds, Fishes, Amphibians and Reptiles
Refinement and Environmental Enrichment for All Laboratory Animals [including primates]
Environmental Enrichment Information Resources for Laboratory Animals

             in the databases and bibliographies section below.

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Species-Specific Requirements for Enrichment

Exercise for Dogs

"...Research facilities must develop, document, and follow an appropriate plan to provide dogs with the opportunity for exercise85 The plan must include written standard procedures to be followed in providing the opportunity for exercise."
              AWA Regulations. Part 3. Standards. A73.8 Exercise for dogs.

"Comfortable quarters for dogs in research institutions." Hubrecht RC. 2002. In Comfortable Quarters for Laboratory Animals, 9th Edition. Reinhardt V and Reinhardt A, eds. Animal Welfare Institute. Washington, DC.
Well-tested refinement options for the housing and handling of laboratory dogs are outlined. The following issues are addressed in detail: Space considerations and minimum space allowances, social housing, exercise, structures and enrichment within the dog enclosure, social interaction of dogs with animal care staff, minimization of stress during interactions between people and dogs, noise in kennels, and dog supply and re-homing.
"Correlates of pen size and housing conditions on the behaviour of kennelled dogs." Hubrecht RC, Serpell JA and Poole TB.1992. Applied Animal Behaviour Science 34:365-383.
Behavioral data were collected from solitary and group-housed dogs [of different breeds] from animal shelters and laboratories. "Solitary dogs were more inactive and spent more time in non-social repetitive locomotory behaviour categories." Dogs housed in pens with spacious, complex outdoor runs were more active and engaged in more species-typical locomotory behaviors than dogs kept in small and barren standard pens.
Guidelines for the Care and Housing of Dogs in Scientific Institutions. 1999. NSW Agriculture. Orange, NSW, Australia.
Guidelines on exercise pen design; exercising and contact with humans apart from normal husbandry procedures are spelled out. "Regular exercise allows for dogs to increase their range of behaviours... The ideal time for social interaction [with humans] is during the exercise period....The minimum exercise period should be 30 minutes for healthy dogs...Group-housed dogs should be exercised as a group..."
"A Novel approach for addressing enrichment and exercise for dogs in a teaching institution." Hammer JG. 2001, Lab Animal 30(7), 26-29.
An IACUC approved, successfully tested [with four beagle dogs] program to foster positive human-animal interactions [a retirement home was visited on a regular basis] and exercise [via preparatory training program] is described.

Environmental Enhancement for Primates

"...Research facilities must develop, document, and follow an appropriate plan for environmental enhancement adequate to promote the psychological well-being of nonhuman primates". The physical environment in the primary enclosures must be enriched by providing means of expressing noninjurious species-typical activities."
AWA Regulations. Part 3. Standards. A73.81 Environmental enhancement to promote psychological well-being.

* Environmental Enrichment and Refinement for Nonhuman Primates Kept in Research Laboratories: A Photographic Documentation and Literature Review. Reinhardt V and Reinhardt A. 3rd edition. 2008. Animal Welfare Institute. Washington, DC . Available free from Animal Welfare Institute, PO Box 3650, Washington, DC 20007.
A collection of annotated photos dealing with all aspects of environmental enrichment including refinement of housing and handling conditions for all nonhuman primate species. "Sharing the same roots makes it easy for any compassionate human primate to make life easier for a nonhuman primate subjected to biomedical research." A comprehensive bibliography is appended to this document.
The Psychological Well-Being of Nonhuman Primates. Committee on Well-Being of Nonhuman Primates. 1998. Institute for Laboratory Animal Research Commission on Life Sciences National Research Council. National Academy Press. Washington, DC.
Concise guidelines for the adequate housing and handling of captive nonhuman primates. Criteria of psychological well-being are: 20 "Appropriate social companionship; opportunities to engage in behavior related to foraging, exploration, and other activities appropriate to the species, age, sex, and condition of the animal; housing that permits suitable postural and locomotor expression; interactions with personnel that are generally positive and not a source of unnecessary stress."
"Social enhancement for adult nonhuman primates in research laboratories: A review." Reinhardt V and Reinhardt A. 2000. Lab Animal 29(1), 34-41.
Comprehensive review of safe, effective and inexpensive options (pair-housing, human interaction, training to cooperate during procedures) to address the social needs of adult nonhuman primates in accordance with the stipulations set forth in the Animal Welfare Act.
"Social-housing of previously single-caged macaques: What are the options and the risks?" Reinhardt V, Liss C and Stevens C. 1995. Animal Welfare 4, 307-328.
"The published data show that previously single-caged macaques can be transferred to social housing adequate for the species ... without undue risk to individual animals" and without interfering with husbandry and common research protocols.

See also

   Environmental Enrichment for Primates: Annotated Database...
   Annotated Bibliography on Refinement and Environmental Enrichment for Primates ...

           in the databases and bibliographies section below.

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"Alternatives to the use of animals in higher education." van der Valk J et al. 1999. ATLA (Alternatives to Laboratory Animals) 27(1), 39-52.
The issues reviewed and discussed include the current use of animals in higher education, the range of alternatives currently available, the advantages and disadvantages of using alternatives in education, methods of disseminating information about alternatives to those involved in education systems, and strategies for evaluating the educational effectiveness of alternatives.
AVAR (Association of Veterinarians for Animal Rights) Alternatives in Education Database. 1990-2000. 2009*. Association of Veterinarians for Animal Rights. Davis, CA.
Searchable database containing audiovisual and textual materials, computer programs, simulations, models and other resources that can be used as alternatives to animals at all levels of education from primary school to the training of medical and veterinary professionals.
From Guinea Pig to Computer Mouse: Alternative methods for a progressive, humane education. Jukes N and Chiuia M. 2nd edition 2003. International Network for Humane Education. Leicester, England.
The book investigates state-of-the-art alternative tools and approaches to support ethical and effective knowledge and skills acquisition within biological science, medical and veterinary medical education.
"Guidelines for humane education: Alternatives to the use of animals in teaching and training." Smith A and Smith K. 2004. The Three Rs at the Beginning of the 21st Century: Proceedings of the Fourth World Congress on Alternatives and Animal Use in the Life Sciences. Balls M, Firmani D and Rowan A, eds, 29-39. ATLA 32, Supplement 1 & 2.
"This paper attempts to clarify the issues raised, presents an overview of the alternatives available with their strengths and weaknesses, and finally offers guidelines for humane education that take into consideration both the practical issues and the feelings of all those involved."
Interniche: The International Website for Humane Education.
Interniche supports progressive science teaching and the replacement of animal experiments by working with teachers to introduce alternatives and with students to support freedom of conscience. The web site is aimed at teachers and students of biological science, veterinary and human medicine, as well as university ethics committee or animal care and use committee members, legislators, and animal welfare advocates. It offers a Alternatives Loan System, a library of products available for free loan anywhere in the world, as well as literature, support and advice for teachers and students.
EURCA: European Resource Centre for Alternatives in Higher Education.
Actively promotes the use of alternatives to using animals in higher education (HE). Aims to provide a mechanism for effective dissemination of information about alternatives to using animals in HE. Is compiling an Alternatives Database that include full description of the alternatives, reviews, user comments and additional educational materials.
The NORINA (A Norwegian Inventory of Alternatives) Database: Audiovisual Alternatives to Laboratory Animals in Teaching. Smith K and Smith A , eds. 2007*. Norwegian School of Veterinary Medicine. Oslo, Norway.
English-language database of audiovisuals for the use of teachers and instructors in the biological sciences. Its primary purpose is to provide an overview of possible alternatives at all educational levels, from elementary school to university. The database consists of more than 3700 entries including computer programs, interactive videos, films, and traditional teaching aids such as slide sets, 3-D models, and classroom charts.
"The PVC-Rat and Other Alternatives in Microsurgical Training." Remie R. 2001. Lab Animal 30(9).
"The number of animals used in educational training programs in experimental microsurgery can be reduced by using artificial devices such as the anastomoses device and the MD PVC-Rat. Such in vitro methods allow development of technical skills, making the transition to in vivo models much easier.... The use of the PVC-Rat model reduces the number of animals used during training of scientists and animal technicians by roughly 90%."

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Databases, Directories, Bibliographies

Alternatives to the Use of Live Vertebrates in Biomedical Research and Testing. A Bibliography with Abstracts. Hudson VW and Nguyen Q. 2002. National Library of Medicine. Bethesda, MD.
A quarterly publication citing techniques that replace or may replace intact vertebrates in biomedical testing to evaluate the toxicological potential of various substances. Very comprehensive. A search engine now enables users to search all issues and/or to limit the search by field, year, and category, and browse the index.
Altweb Pain Management Database. Allen T. 2007*. Altweb Web Site.
"This database includes information about anesthesia and analgesia for most commonly used laboratory animals, including: rats, mice, primates, dogs, cats, rabbits, pigs, guinea pigs, birds, sheep, fish, and exotic species. It provides information about available drugs and the side effects of commonly used drugs. Citations are from publications that have published laboratory animal studies or human clinical studies with relevance to animal research." Contains approximately 10,000 records, most of them with abstracts. It covers the period 1990 to the present, and is updated quarterly. Almost all of the records--98%--have abstracts. Records have been drawn from three major databases: MEDLINE (with records from TOXLINE as well), AGRICOLA, and AGRIS.
AnimalAlt-ZEBET Database. Spielmann H, Grune B, Dorendahl A and Skolik S. 1989, 2006. Zentralstelle zur Erfassung und Bewertung von Ersatz und Erganzungsmethoden zum Tierversuch (ZEBET) [Center for Documentation and Evaluation of Alternative Methods to Animal Experiments]. Berlin, Germany.
Invaluable resource for the literature search. ZEBET is a database of alternative methods (replacement, refinement and reduction) to animal experiments in the English language. It contains over 4300 bibliographical references on more than 125 methods covering the field of biomedicine and related fields. Each record contains a short description of a method in its most important details, i.e. aim, principle, and the stage of development or validation of the method and bibliographical references. An evaluation by ZEBET staff indicates whether the method results in the replacement, reduction or refinement of animal use according to the "3R's." Fields are searchable. The database is hosted by DIMDI where it may be searched free of charge.
Annotated Bibliography on Refinement and Environmental Enrichment for Primates kept in Laboratories. Reinhardt V and Reinhardt A. 2008. 12th Edition. Animal Welfare Institute. Washington, DC.
This bibliography offers practical information on techniques that promote the expression of species-appropriate behavioral and mental activities in captive nonhuman primates. Specifically geared towards animal caregivers, animal technicians, zoo keepers, students and veterinarians. All entries are annotated.
Database on Refinement of Housing and Handling Conditions and Environmental Enrichment for Laboratory Animals: Rodents, Rabbits, Cats, Dogs, Ferrets, Farm Animals, Horses, Birds, Fishes, Amphibians and Reptiles. Reinhardt V and Reinhardt A. 2009*. Animal Welfare Institute. Washington, DC.
More than a thousand annotated entries, 13% full-text, on all aspects of environmental enrichment and refinement of housing and handling conditions of laboratory animals and farm animals used in research. Access to the database is free. It is searchable by citation and keywords and updated at least once every two months.
"Free Databases." FRAME Web Page. 2006*.
Excellent, comprehensive annotated list of databases with links. Includes 3 Rs databases; alternatives in education; cell-line databases; current research; general scientific; normal, transgenic and knockout strains.
Environmental Enrichment Information Resources for Laboratory Animals: Birds, Cats, Dogs, Farm Animals, Ferrets, Rabbits, And Rodents: 1965-1995. Smith CP and Taylor V. 1995. (AWIC Resource Series no. 2). U.S. Department of Agriculture, National Agricultural Library, Animal Welfare Information Center. Beltsville, MD.
Articles and bibliographies covering environmental enrichment techniques for birds, cats, dogs, farm animals, ferrets, rabbits and rodents.
Environmental Enrichment for Primates: Annotated Database on Environmental Enrichment and Refinement of Husbandry for Nonhuman Primates. Reinhardt V and Reinhardt A. 2009*. Animal Welfare Institute. Washington, DC.
More than 1500 annotated entries 22% full-text on all aspects of environmental enhancement, including social housing, feeding enrichment, inanimate enrichment and training to cooperate during procedures. Access to the database is free. It is searchable by citation and keywords including species names and is updated at least once every two months.
Environmental Enrichment for Nonhuman Primates Resource guide. Adams K. 2009. National Agricultural Library, Animal Welfare Information Center, Beltsville, MD.
"This publication updates and expands AWIC's Environmental Enrichment for Nonhuman Primates Resource Guide. It covers literature published from 1999-Jan 2009. The bibliographic chapters are divided into subject areas that cover the concept of environmental enrichment, enrichment for nonhuman primates overall, abnormal behavior exhibited by nonhuman primates, great apes and gibbons, macaques, old world monkeys other than macaques, marmosets and tamarins, other new world monkeys, lemurs, lorises, and tarsiers, animal training as an enrichment strategy, and books and proceedings from conferences focused on environmental enrichment or nonhuman primate management."
Environmental Enrichment for Rodents and Rabbits: An Annotated Bibliography. Reinhardt A. 2007. Animal Welfare Institute. Washington, DC.
This bibliography offers animal caregivers, animal technicians, veterinarians, and students guidance to practical information on refinement and environmental enrichment for rodents and rabbits kept in research institutions.
"Free web resources on alternatives." Donnelly TM. 2004. Lab Animal 33(3), 46-48.
Access to many online databases for alternatives searches requires a paid subscription and these fees may be expensive for small or not-for-profit institutions. The author provides a list of free sites that can be used to fulfill the legal requirement for an alternatives search.
Institute for In Vitro Sciences . IIVS Publications: Bibliography. 2009*
Searchable bibliography of in vitro resources with access to online documents . Articles include the following categories: eye, ocular; skin ; photoxicity; percutaneous penetration; acute toxicity; validation; alternative methods.
Practical Enrichment Options for Animals Kept in Research Institutions. Reinhardt A. 2009*. Animal Welfare Institute. Washington, DC.
This database disseminates enrichment ideas and practical tips from the "Laboratory Animals Refinement and Enrichment Forum" and from other published information.
Refinement and Environmental Enrichment for All Laboratory Animals. Reinhardt V and Reinhardt A. 2009*. Animal Welfare Institute. Washington, DC.
This information resource is a merger of the two databases on refinement & enrichment for non-primate and primate laboratory animals. It contains nearly three thousand annotated entries, 17% full-text, on all aspects of refinement of housing and handling conditions and environmental enrichment for ALL animals kept in research, testing and teaching institutions. Access to the database is free. It is searchable by citation and keywords and updated at least once every two months.
ECVAM Database Service on Alternative Methods to Animal Experimentation. ECVAM (European Centre for the Validation of Alternative Methods).
DB-ALM provides factual and evaluated information on advanced non-animal test development and validation for toxicology assessments coming from a wide range of international information sources. It includes various databases on method descriptions, validation studies, INVITTOX protocols, compounds and test results, ECVAM workshop reports.

Search Engines, Search Guidelines

"A guide to searching for alternatives to the use of laboratory animals." Bottrill K. FRAME Web Site.
Very useful and comprehensive guide, including basic principles for searching the Internet or any online database, comparison of search engines, suggestions for how to approach a search on the Three Rs; a description, including links, of some of the databases which can be accessed free on the Internet, as well as a listing of commercial databases and database hosts of potential relevance.
"The search for refinement alternatives: When you've just got to use animals." Kreger, MD. 2000. Lab Animal 29(4), 22-25, 28-29.
Tips for researchers and IACUCs on how to conduct a literature search for refinement. "Refinements to animal-use protocols can help reduce animal pain and distress, thus producing cleaner data. Yet, most researchers neglect a refinement search, despite legal mandates, because the information is not readily available. What's more, IACUCs may have difficulty assessing researchers' refinement searches. The author offers some solutions."
"Tips for searching for alternatives to animal research and testing." Smith CP. 1994. Lab Animal 23(3), 46-48.
"Investigators can assist information specialists who perform the search by being prepared to give precise and specific information about their research or testing procedures." The type of information the investigator may be asked to provide is listed, and the two phases of a search strategy, 1. reduction and refinement, and 2. replacement, are delineated. Sample searches are given. Worksheets (requesting information that the researcher must provide in order to run a multi-database literature search for alternatives) with instructions and a search summary form can be found at:

Specialized In Vitro Replacement Resources

Skin irritation
Alternatives to Skin Irritation Testing in Animals. Huggins, J. compiler. Searchable database containing approx. 360 citations with abstracts.

Monoclonal antibodies

Altweb special section on monoclonal antibodies, ALTWEB

Antibody resource page


Resource Lists of In Vitro MAB Producers
Companies and Institutes Providing New Technologies in Mabs. Jensen A and Smith CP, compilers.

Introduction and resources, various in vitro listings of facilities that produce MAbs.

In the context of the Three Rs this site might assist scientists to identify monoclonal antibodies produced in vitro rather than in vivo and to avoid using animals to produce an antiserum that is already available.

Where to get in vitro mabs: academic core centers and commercial facilities

AWIC Selected list of company and institute resources in Mabs with annotations

MEIC (Multicentre Evaluation of In Vitro Cytotoxicity) The MEIC in vitro database contains in vitro data for the 50 MEIC reference chemicals, as well as the methodology of the used in vitro assays.

In Vitro Tests
INVITTOX protocols In Vitro Testing Industrial Platform (Europe) Up-to-date listing of in vitro tests currently available.

Note: * Date when last accessed while compiling the bibliography. Web sites and databases are updated regularly.

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Compiled by Annie and Viktor Reinhardt, Animal Welfare Institute and reviewed by Barbara Orlans, Kennedy Institute of Ethics.

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