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. 
Gomes, D., McSweeney, L., Santos, M. 2019. Effects of environmental enrichment techniques on stereotypical behaviours of captive Sumatran tigers: A preliminary case study. Journal of Animal Behaviour and Biometeorology 7(4), 144-148.

Wild animals are maintained in Zoological facilities for purposes of education, conservation, research, and recreation. Several studies have proven that the surroundings of an animal's artificial habitat, as well as environmental enrichment techniques, are factors...

Lutz, C. K., Brown, T. A. 2018. Porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). JAALAS 57(2), 138-142.

Effective environmental enrichment is used by animals, promotes species-typical behavior, and decreases abnormal behavior. Porches attached to the front of an animal's cage provide additional space, perching opportunities, and a better view of the surroundings...

Cabana, F., Maguire, R., Hsu, C-D. et al. 2018. Identification of possible nutritional and stress risk factors in the development of marmoset wasting syndrome. Zoo Biology 37(2), 98–106.

Marmoset wasting syndrome (MWS) describes a series of symptoms in callitrichids that lead to general weakness and a failure to thrive in captive conditions such as zoological institutions. Though the cause of MWS has not...

Brown, T. A., Lutz, C. K., 2018. An assessment of porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). American Journal of Primatology 80(S1), 18 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #21).

Effective environmental enrichment encourages usage, promotes species‐typical behaviors, and/or decreases abnormal behaviors. Porches are small cages that attach to the primary cage of an animal to provide additional space and a better view of the...

Perlman, J. E., Martin, A. L., Bloomsmith, M. A., 2018. Increases in feeding and destructible enrichment distribution in caged rhesus macaques (Macaques mulatta) provide some behavioral benefits. American Journal of Primatology 80(S1), 19 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #24).

It is important to evaluate the effectiveness of environmental enrichment in meeting behavioral goals (e.g., decreasing abnormal behavior) and in making the best use of limited facility resources (e.g., money, personnel time). One/zero behavioral data...

Woelffer, S., Ace, L., Sullivan, J. et al., 2018. Enhanced physical environment in single-housed macaques: A long-term usage profile of cage extensions. American Journal of Primatology 80(S1), 19-20 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #25).

Social housing is always preferred in the research environment; however, single housing is sometimes necessitated by scientific objectives or social incompatibility. In these cases, other environmental enhancements are developed to provide indirect social interactions. We...

Yoshimoto, T., Takahashi, E., Yamashita, S. et al. 2018. Larger cages with housing unit environment enrichment improve the welfare of marmosets. Experimental Animals 67(1), 31-39.

The provision of adequate space for laboratory animals is essential not only for good welfare but accurate studies. For example, housing conditions for primates used in biomedical research may negatively affect welfare and thus the...

Perdue, B. M., Beran, M. J., Washburn, D. A. 2018. A computerized testing system for primates: Cognition, welfare, and the Rumbaughx. Behavioural Processes 156, 37-50.

Innovations in apparatus technology come about for a variety of reasons such as the need to use the same methodology with various species, the opportunity to present dynamic and carefully controlled stimuli, the goal of...

Heyworth, C., Olivo, D. 2018. Environmental and psychological enrichment for NHPs reimagined and repurposed. Laboratory Animal Science Professional 5(4) (December), 39-43.

This article describes creative enrichment ideas for nonhuman primates, including celery stalks embedded with seeds; paper rolled into tubes, braided and filled with fruit and seeds; pineapple crowns loaded with treats; dry spaghetti noodles coated...

Coursodon, P., Cox, L., Largent-Milnes, T. M. et al. 2018. Enhanced environmental enrichment strategies for retired rhesus macaques. Laboratory Animal Science Professional 6(2) (June), 41-43.

One challenge in providing enrichment to NHP arises following completion of their assigned studies (retired) when there tends to be a sudden decrease in provision of daily human interaction and overall stimulation that results from...

Iske, C. J., Morris, C. L., Colpoys, J. D. et al. 2018. Nutrient evaluation of a pork by-product and its use as environmental enrichment for managed large exotic cats. PLOS ONE 13(9), e0202144.

North American zoological institutions typically feed ground raw meat diets to large exotic cats. These diets typically are nutritionally complete, but lack physical properties characteristic of whole prey. Lack of mastication and prey manipulation may...

Cannon, T. 2017. Tailored enrichment strategies and stereotypic behaviour in captive individually-housed macaques (Macaca spp.). Canopy 17(2), 13-16.

In this study, I combine both physiological and behavioural measures of well-being to comprehensively assess the unique needs of individually-housed captive macaques (Macaca spp.) at OPR Coastal Primate Sanctuary in Longview, WA, with the aim...

Palmer, S. 2017. Rescue-Enrich-Release: The environmental enrichment program for three species of captive primates at Colobus. Canopy 17(2), 27-30.

It is widely known that the psychological wellbeing of captive animals can become compromised by a captive environment that lacks proper environmental stimulation. Environmental enrichment programs have become the norm in captive environments yet research...

Alligood, C. A., Dorey, N. R., Mehrkam, L. R. et al. 2017. Applying behavior-analytic methodology to the science and practice of environmental enrichment in zoos and aquariums. Zoo Biology 36(3), 175–185.

Environmental enrichment in zoos and aquariums is often evaluated at two overlapping levels: published research and day‐to‐day institutional record keeping. Several authors have discussed ongoing challenges with small sample sizes in between‐groups zoological research and...

Damasceno, J., Genaro, G., Quirke, T. et al. 2017. The effects of intrinsic enrichment on captive felids. Zoo Biology 36(3), 186–192.

Environmental enrichment is a well‐known technique, which has been used to enhance the welfare of captive animals. The aim of this study is to investigate how three different forms of intrinsic enrichment, namely, a hay...

Carlson, A., Allen, C., Skoumbourdis, E. et al. 2017. Cooked food for non-human primates: A discussion by the Laboratory Animal Refinement & Enrichment Forum. Animal Technology and Welfare 16(2), 124-126.

"Do any of you give cooked food like pasta, potatoes or vegetables to non-human primates? What’s your experience? Do the animals benefit from cooked food; do they like it; does it affect their health in...

Coleman, K., Novak, M. A. 2017. Environmental enrichment in the 21st century. ILAR Journal 58(2), 295-307.

More than a quarter of a century has elapsed since the Animal Welfare Act mandated that research facilities develop and follow a plan to promote the psychological well-being of captive primates. Since passage of this...

Adams, S. C., Guyot, C. M., Berry, K. M. et al. 2017. Hypercortisolemia and depressive-like behaviors in a rhesus macaque (Macaca mulatta) involved in visual research. Comparative Medicine 67(6), 529–536.

A 10-y-old cranially implanted rhesus macaque (Macaca mulatta) involved in visual research was presented for dull mentation and weight loss. Physical examination revealed alopecia and poor body conditioning, and bloodwork revealed marked hypercortisolemia (23 μg/dL)...

Phillips, C. J. C., Tribe, A., Lisle, A. et al. 2017. Keepers' rating of emotions in captive big cats, and their use in determining responses to different types of enrichment. Journal of Veterinary Behavior 20, 22-30.

Effective identification of emotional states in captive big cats by keepers is important for them to be able to reduce the risks of abnormal behavior by providing appropriate enrichment strategies. In an initial study, 29...

Perlman, J. E., Chace, K. E., Jordan, J. et al. 2017. High-density polyethylene artificial turf is a durable foraging substrate for rhesus macaques. Laboratory Animal Science Professional 5(4) (December), 40-43.

In the wild, rhesus monkeys and other macaque species spend a majority of their waking hours searching for and eating food. For monkeys housed in runs and in caged settings, making species-typical foraging tasks available...

Sands, C., Evans, C., Buckmaster, C. A. 2017. The grooming sleeve: Encouraging conspecific-like behavior and strengthening the human-animal bond. Laboratory Animal Science Professional 5(2) (June), 52-53.

The act of grooming has been found to greatly decrease stress, heart rate, and cortisol levels in nonhuman primates; this decrease in stress and cortisol is seen in the animal being groomed, as well as...

Cavallaro, J., Stevens Jr., R. W., Wilson, B. et al. 2017. Social housing pig tail macaques in repurposed chimpanzee enclosures. Laboratory Animal Science Professional 5(2) (June), 60-61.

As chimpanzees are retired from research, enclosures such as the Primadomes™ become available for repurposing for other monkey species. However, modifications are necessary to meet specific monkey species needs, and considerations for animal handling and...

Slaney, H. 2017. Using domestic animals as tiger enrichment. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 44(2), 24-27.

At Colchester Zoo we have a well established but evolving enrichment program, using many different ideas and techniques for our many different species. One form of enrichment we use is the presence of our domestic...

de Groot, B., Cheyne, S. M. 2016. Does mirror enrichment improve primate well-being? Animal Welfare 25(2), 163-170.

Primates are highly social animals and appropriate enrichment is required to ensure their psychological well-being. Mirrors are sometimes used as social or sensory environmental enrichment. In this paper we investigate the suitability of mirrors as...

Cannon, T. H., Heistermann, M., Hankison, S. J. et al. 2016. Tailored enrichment strategies and stereotypic behavior in captive individually housed macaques (Macaca spp.). Journal of Applied Animal Welfare Science 19(2), 171-182.

The welfare of nonhuman animals in captivity is widely dependent on the natural psychological, physical, and behavioral needs of the animals and how adequately these needs are met. Inability to engage in natural behaviors can...