Refinement Database

Database on Refinement of Housing, Husbandry, Care, and Use of Animals in Research

This database, created in 2000, is updated every four months with newly published scientific articles, books, and other publications related to improving or safeguarding the welfare of animals used in research.

Tips for using the database:

  • This landing page displays all of the publications in the database.
  • Use the drop-down menus to filter these publications by Animal Type, Setting, and/or Topic.
  • Clicking on a parent category (e.g., Rodent) will include publications relating to all the items in that category (e.g., Chinchilla, Gerbil, Guinea Pig, etc.).
  • You may also add a keyword to further narrow your search.
  • Please note that at this time, only publications dated 2010 or later (with some exceptions) can be filtered by Animal Type and Topic, and only publications dated 2020 or later (with some exceptions) can be filtered by Setting. Most publications older than 2010 can only be searched by keyword. 
Hrapkiewicz, K., Colby, L. A., Denison, P. 2013. Clinical Laboratory Animal Medicine: An Introduction (4th Ed). Wiley-Blackwell, Ames, IA.

Clinical Laboratory Animal Medicine: An Introduction, Fourth Edition offers a user-friendly guide to the unique anatomy and physiology, care, common diseases, and treatment of small mammals and nonhuman primates. Carefully designed for ease of use...

Dragon, M. 2013. Getting on the same page: Using a checklist to communicate environmental enrichment. Enrichment Record 15, 5-6.

Multiple species, study protocols and user needs make it difficult to develop a one-size-fits-all approach to standardizing enrichment. Fortunately, it turns out that there is a very simple solution to the complex issue of getting...

Grimm, J. W., Weber, R., Barnes, J. et al. 2013. Brief exposure to novel or enriched environments reduces sucrose cue-reactivity and consumption in rats after 1 or 30 days of forced abstinence from self-administration. PLOS ONE 8(1), e54164.

Environmental enrichment (EE) reduces drug and sucrose cue-reactivity in rats. In a previous study we reported that 1 month of EE (large cage, toys, and social cohorts) significantly reduced sucrose cue-reactivity. In the present study...

Fares, R. P., Belmeguenai, A., Sanchez, P.E. et al. 2013. Standardized environmental enrichment supports enhanced brain plasticity in healthy rats and prevents cognitive impairment in epileptic rats. PLOS ONE 8(1): e53888.

Environmental enrichment of laboratory animals influences brain plasticity, stimulates neurogenesis, increases neurotrophic factor expression, and protects against the effects of brain insult. However, these positive effects are not constantly observed, probably because standardized procedures of...

Azar, T. A., Sharp, J. L., Lawson, D. M. 2012. Effects of cage enrichment on heart rate, blood pressure, and activity of female Sprague-Dawley and spontaneously hypertensive rats at rest and after acute challenges. JAALAS 51(3), 339-344.

Here we sought to determine whether a nonsocial cage enrichment program, identical to one we previously used with male rats, was effective in reducing heart rate or systolic blood pressure (SBP) in female Sprague-Dawley rats...

Winnicker, C., Gaskill, B. 2012. Using enrichment to improve welfare and reduce suffering. Enrichment Record 12, 16-19.

European Directive 2010/63/EU requires that accommodation and care are refined so as to minimize suffering, and that the lifetime experience of the animal is taken into account when assessing the actual severity of procedures. So...

Froberg-Fejko, K. M., Lecker, J. L. 2012. Going back to nature: The benefits of wood enrichment. Lab Animal 41(11), 345-347.

Environmental enrichment can be defined as altering the living environment of captive animals in order to provide them with opportunities to express more of their natural behavioral repertoire. The challenge of providing effective enrichment in...

Rollin, B. E. 2012. ENRICHMENT as a moral presupposition of animal research. Enrichment Record 10, 13-16.

Enrichment is therefore not the bighearted largess that much of the research community seems to believe it is. Rather, it represents an obvious step towards creating a decent life for research animals and minimizing avoidable...

Bratcher, N., Clemons, D., Medina, L. 2012. History of enrichment in the ILAR Guide for the Care and Use of Laboratory Animals. Enrichment Record 12, 10-12.

Throughout the nearly 50 year history of the Institute for Laboratory Animal Research (ILAR) Guide, little attention or content was allocated to the subject of enrichment until the current (8th) edition (NRC 2011). Although animal...

Luchins, K. R., Baker, K. C., Gilbert, M. H. et al. 2011. Manzanita wood: A sanitizable enrichment option for nonhuman primates. JAALAS 50(6), 884-887.

Wooden objects are often used as nonhuman primate enrichment to provide variety and novelty, promote exploratory behavior, and supply an outlet for curiosity. However, concerns have been raised regarding the ability to sanitize wood by...

Abou-Ismail, U. A., Mahboub, H. D. 2011. The effects of enriching laboratory cages using various physical structures on multiple measures of welfare in singly-housed rats. Laboratory Animals 45(3), 145-153.

The single housing of laboratory rats may be recommended in some situations such as hypothesis-driven or test-specific studies, during electroencephalogram recording of phases of sleep and after surgical procedures. However, as single housing of laboratory...

Akiyama, K., Sutoo, D. 2011. Effect of different frequencies of music on blood pressure regulation in spontaneously hypertensive rats. Neuroscience Letters 487(1), 58-60.

The effect of different frequencies of music on brain function was investigated through measurement of blood pressure in spontaneously hypertensive rats (SHR). Previous studies indicated that exposure to Mozart's music (K. 205) leads to increased...

Abou-Ismail, U. A. 2011. Are the effects of enrichment due to the presence of multiple items or a particular item in the cages of laboratory rat? Applied Animal Behaviour Science 134(1-2), 72-82.

Although the effects of environmental enrichment on laboratory rodents have been extensively described, it is not yet known whether these effects were simply due to the presence of multiple items in the cage or due...

Witt, S. L., Plews, C. A., Ruppert, G. et al. 2011. Nylon cylinder: Safe and cost-effective chewable rat enrichment. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 782 (Abstract #P174).

Offering enrichment to stimulate chewing behavior in rats has been found to promote psychologic and physiologic wellbeing. While there are many commercially produced nylon products available for use as chewable enrichment, these items are costly...

Neubauer, T., Buckmaster, C. 2011. Decline in aggression in cotton rats through enrichment. Tech Talk [The Newsletter for Laboratory Animal Science Technicians] 16(4), 2-3.

The tubes provide shelter and nesting material to the rats, allowing them to exhibit species-specific behaviors. The change in the animals' behavior has been overwhelming. The rats are much less aggressive; in one year, fight...

Krohn, T. C., Salling, B., Kornerup Hansen, A. 2011. How do rats respond to playing radio in the animal facility? Laboratory Animals 45(3), 141-144.

In the animal facility, a range of different sounds are present. On the one hand, rats and humans will regard sound and noise differently even within the audible range, but on the other hand mice...

Brydges, N. M., Leach, M., Nicol, K. et al. 2011. Environmental enrichment induces optimistic cognitive bias in rats. Animal Behaviour 81(1), 169-175.

People's affective or emotional state can alter their cognitive processing, biasing interpretation of ambiguous stimuli. Those in a more positive state interpret such stimuli in a more optimistic manner than those in a negative state...

Špinka, M., Wemelsfelder, F. 2011. Environmental challenge and animal agency. Animal Welfare 27–43.

Challenges are there to be overcome – seen usually as problems to avoid rather than as opportunities to enjoy. However, for humans a life without challenge would be likely to be dull and boring, lacking...

Abou-Ismail, U. A., Burman, O. H. P., Nicol, C. J. et al. 2010. The effects of enhancing cage complexity on the behaviour and welfare of laboratory rats. Behavioural Processes 85(2), 172-180.

This experiment was carried out to investigate the long-term effects of enhancing cage complexity on behavioural measures of welfare in laboratory rats. We housed 72 rats in groups of four in either ‘enriched’ or ‘unenriched’...

Vyas, D., Mayfield, K. L. 2010. Visual aid for creating enrichment items. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 705 (Abstract #P76).

Enrichment devices are administered to laboratory animals to reduce abnormal behaviors and to promote species typical behaviors (for example, foraging and nest building). With a diverse collection of species that require numerous enrichment options, a...

Turner, P. V., Ovari, J., Pinelli, C. et al. 2010. Long-term effects of housing and enrichment on affective behavior and responsiveness of Sprague-Dawley rats. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 658-659 (Abstract #PS12).

Most rodent studies evaluate different caging paradigms over short periods of time, which may not be realistic for typical colony settings. Inappropriate housing may lead to boredom, aggression, stereotypies, and altered metabolism, which in turn...

Newman, A. 2010. A simple improvement of rodent tunnels for environmental enrichment. Animal Technology and Welfare 9, 57-58.

We found commercially available rodent tunnels are too small in diameter when the rat reaches a size

Mikkelsen, L. F., Sørensen, D. B., Krohn, T. et al. 2010. Clinical pathology and cardiovascular parameters are not influenced by housing rats under increased environmental complexity. Animal Welfare 19(4), 449-460.

Since the release of the revised Appendix A from the Council of Europe for housing of laboratory animals there have been claims that laboratory animals should be housed under more complex conditions; known popularly as...

Lett, G. S. 2010. Measuring the impact of animal enrichment on research results. Enrichment Record 2, 6-7.

My take on this message is that the research community is gathering enough data from laboratory animals under a variety of environmental conditions, but we are not recording and/or sharing enough information about the animal...

Lett, G. S., Patterson-Kane, E. G. 2010. Environmental enrichment fights cancer and improves research results - What now for the biomedical researcher? Enrichment Record 5, 4-6.

The article, “Environmental and Genetic Activation of a Brain-Adipocyte BDNF/Leptin Axis Causes Cancer Remission and Inhibition,” was first published in Cell on July 8, and quickly echoed by online editions of major journals including The...