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. 
Cox, R. J., Nol, P., Ellis, C. K. et al. 2019. Research with agricultural animals and wildlife. ILAR Journal 60(1), 66-73.

In fiscal year 2016, agricultural animals such as swine, sheep, goats, and cattle represented 10% of the 820 812 animals used in USDA-regulated research. In addition to traditional agricultural animals, research studies using captive wildlife...

Wooddell, L. J., Beisner, B., Hannibal, Darcy L. et al. 2019. Increased produce enrichment reduces trauma in socially-housed captive rhesus macaques (Macaca mulatta). American Journal of Primatology 81(12), e23073.

Due to primate adaptations for sociality, captive rhesus macaques have optimal welfare and utility as a biomedical model when they can be maintained in outdoor social groups. As a despotic species; however, aggression can result...

Schmitt, V. 2019. Implementing portable touchscreen-setups to enhance cognitive research and enrich zoo-housed animals. Journal of Zoo and Aquarium Research 7(2), 50-58.

To understand the evolutionary development of cognition, comparing the cognitive capacities of different animal species is essential. However, getting access to various species with sufficient sample sizes can be very challenging. Zoos, housing large ranges...

Perez, B. C., Mehrkam, L. R., Foltz, A. R. et al. 2018. Effects of enrichment presentation and other factors on behavioral welfare of pantropical spotted dolphin (Stenella attenuata). Journal of Applied Animal Welfare Science 21(2), 130-140.

Environmental enrichment is a crucial element of promoting welfare for animals in captivity. However, enrichment programs are not always formally evaluated for their efficacy. Furthermore, there is little empirical evidence of enrichment evaluation for species...

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...

Fuller, G., Murray, A., Thueme, M. et al. 2018. Behavioral and hormonal responses to the availability of forage material in Western lowland gorillas (Gorilla gorilla gorilla). Zoo Biology 37(1), 23–34.

We investigated how forage material affects indicators of welfare in three male Western lowland gorillas (Gorilla gorilla gorilla) at the Detroit Zoo. In addition to their maintenance diet and enrichment foods, the gorillas generally received...

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...

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...

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)...

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...

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...