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. 
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...

Shelton, K. A., Nehete, B. P., Chitta, S. et al. 2019. Effects of transportation and relocation on immunologic measures in cynomolgus macaques (Macaca fascicularis). JAALAS 58(6), 774–782.

NHP are a small, but critical, portion of the animals studied in research laboratories. Many NHP are imported or raised at one facility and subsequently moved to another facility for research purposes. To improve our...

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...

Borgmans, G., Palme, R., Sannen, A., et al. 2018. The effect of environmental provisioning on stress levels in captive green anole (Anolis carolinensis). Animal Welfare 27(1), 35-46.

In response to an increased awareness concerning the welfare of captive animals, several studies have investigated the effect of provisions on stress levels in model species, such as small mammals, birds and fish. In contrast...

Costa, R., Sousa, C., Llorente, M. 2018. Assessment of environmental enrichment for different primate species under low budget: A case study. Journal of Applied Animal Welfare Science 21(2), 185-199.

The 2011 European Union Zoo Inquiry presented evidence that most zoos fail to achieve adequate levels of nonhuman animal welfare. Appropriate environmental enrichment (EE) can play a role in the promotion of welfare. However, financial...

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...

Grunauer, P. P., Walguarnery, J. W. 2018. Relative response to digital tablet devices and painting as sensory enrichment in captive chimpanzees. Zoo Biology 37(4), 269–273.

Digital devices, including tablet computers and other touchscreens, can potentially serve as flexible and convenient means for providing behavioral enrichment activities to captive primates. Despite increased interest in incorporating technology into enrichment programs, no direct...

Shapiro, M. E., Shapiro, H. G., Ehmke, E. E. 2018. Behavioral responses of three lemur species to different food enrichment devices. Zoo Biology 37(3), 146–155.

Environmental enrichment is a tool used to promote the welfare and well‐being of captive animals by encouraging the display of species‐specific behaviors and reducing the stress or boredom induced by captive environments. Lemurs are highly...

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...

Baker, B., Taylor, S., Montrose, V. T. 2018. The effects of olfactory stimulation on the behavior of captive ring-tailed lemurs (Lemur catta). Zoo Biology 37(1), 16–22.

Ring‐tailed lemurs reside in many animal collections worldwide. Lemur welfare may be a cause of concern due to some captive individuals exhibiting stereotypic behavior. Despite these concerns, there has been little exploration of methods of...

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...

Cornelius, N., Enstam‐Jaffe, K. Minier, D. et al., 2018. Increasing captive chimpanzee (Pan troglodytes) engagement with multi-step cognitive enrichment. American Journal of Primatology 80(S1), 19 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #23).

Environmental enrichment enhances the psychological well‐being of animals and is therefore a vital part of the husbandry of captive animals. Since chimpanzees are a cognitively complex species, they may especially benefit from enrichment programs that...

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...

Wallace, E. K., Altschul, D., Körfer, K. et al. 2017. Is music enriching for group-housed captive chimpanzees (Pan troglodytes)? PLOS ONE 12(3), e0172672.

Many facilities that house captive primates play music for animal enrichment or for caregiver enjoyment. However, the impact on primates is unknown as previous studies have been inconclusive. We conducted three studies with zoo-housed chimpanzees...

Nehete, P. N., Shelton, K. A., Nehete, B. P. et al. 2017. Effects of transportation, relocation, and acclimation on phenotypes and functional characteristics of peripheral blood lymphocytes in rhesus monkeys (Macaca mulatta). PLOS ONE 12(12), e0188694.

Nonhuman primates from domestic sources constitute a small, but critical, proportion of animals studied in research laboratories. Many of these nonhuman primates are raised at one facility and subsequently transported/relocated to another facility for research...

Cinque, C., De Marco, A., Mairesse, J. et al. 2017. Relocation stress induces short-term fecal cortisol increase in Tonkean macaques (Macaca tonkeana). Primates 58(2), 315-321.

The level of glucocorticoids, especially if obtained from noninvasive sampling, can be used as an index of animal well-being, allowing evaluation of the animal’s response to environmental modifications. Despite evidence that these hormones play a...

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...