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...

Špinka, M. 2019. Animal agency, animal awareness and animal welfare. Animal Welfare 28(1), 11–20.

In nature, animals need to actively engage with the environment in order to prosper in survival and reproduction. Hence, agency is a central adaptive characteristic of animal life. In this paper, I propose that from...

Hacker, C. E., Miller, L. J., Schulte, B. A. 2018. Examination of enrichment using space and food for African elephants (Loxodonta africana) at the San Diego Zoo Safari Park. Animal Welfare 27(1), 55-65.

Concern for elephant welfare in zoological facilities has prompted a number of exhibit and management modifications, including those involving enrichment. Knowledge of how these changes impact indicators of welfare, such as elephant movement and behaviour...

Wagman, J. D., Lukas, K. E., Dennis, P. M. et al. 2018. A work-for-food enrichment program increases exploration and decreases stereotypies in four species of bears. Zoo Biology 37(1), 3–15.

Zoo‐housed bears are prone to exhibiting stereotypic behaviors, generally considered indicators of negative welfare. We explored the effects of a variable‐time feeding enrichment schedule on behavioral indicators of welfare in four bear species at Cleveland...

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...

French, F., Mancini, C., Sharp, H. 2018. High tech cognitive and acoustic enrichment for captive elephants. Journal of Neuroscience Methods 300, 173-183.

This paper investigates the potential for using technology to support the development of sensory and cognitive enrichment activities for captive elephants. It explores the usefulness of applying conceptual frameworks from interaction design and game design...

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...

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...

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...

Dupont, M. 2017. An investigation into whether food-based environmental enrichment will increase the activity levels of Alaotran gentle lemurs (Hapalemur alaotrensis) at Birmingham Wildlife Conservation Park. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 44(1), 14-17.

Excessive weight gain and obesity is becoming a more frequent problem affecting captive lemurs. Animals have evolved to survive in specific environments, causing them to perform species-specific behaviours which animals are highly motivated to perform...

Cooper, J. E., Hull, G. 2017. Gorilla Pathology and Health: With a Catalogue of Preserved Materials. Elsevier/Academic Print, London, UK.

Gorilla Pathology and Health: With a Catalogue of Preserved Materials consists of two cross-referenced parts. The first, the book itself, is a review of pathological changes and tissue responses in gorillas (Gorilla gorilla and G...

Roth, T. S., Bionda, T. R., Sterck, E. H. M. 2017. Recapturing the canopy: Stimulating Bornean orang-utan (Pongo pygmaeus) natural locomotion behaviour in a zoo environment. Journal of Zoo and Aquarium Research 5(1), 16-24.

Orang-utans are the largest mainly arboreal animal: wild orang-utans rarely come to the forest floor. In contrast, the locomotion behaviour of captive orang-utans encompasses more time on the ground and they spend less time on...

Monreal-Pawlowsky, T., Marco-Cabedo, V., Manteca, X. et al. 2017. Environmental enrichment facilitates release and survival of an injured loggerhead sea turtle (Caretta caretta) after ten years in captivity. Journal of Zoo and Aquarium Research 5(4), 182-186.

In June 2006 a loggerhead sea turtle (Caretta caretta) was admitted to a rescue centre on the Mediterranean coast with severe fishing net entanglement in its fore right flipper. The flipper could not be saved...

Clark, F. 2017. Cognitive enrichment and welfare: Current approaches and future directions. Animal Behavior and Cognition 4(1), 52–71.

Cognitive enrichment” is a subset of enrichment that has gained interest from researchers over the past decade, particularly those working in zoos. This review explores the forms of cognitive enrichment that have been attempted for...

Krebs, B., Watters, J. 2017. Simple but temporally unpredictable puzzles are cognitive enrichment. Animal Behavior and Cognition 4(1), 119–134.

Provision of problem solving opportunities as enrichment for animals considered highly intelligent has increased over the last twenty years, but this emphasis on animals considered intelligent may overlook the need for cognitive challenge in species...

Troxell-Smith, S., Watters, J., Whelan, C. et al. 2017. Zoo foraging ecology: Preference and welfare assessment of two okapi (Okapia johnstoni) at the Brookfield Zoo. Animal Behavior and Cognition 4(2), 187–199.

Applying principles of foraging ecology to zoo-housed animals can positively influence animal behavior, and assist with evaluating exhibit space and design. In this study, we implemented zoo foraging ecology by measuring giving-up densities (GUDs) in...

Brown, J. L., Paris, S., Prado-Oviedo, N. A. 2016. Reproductive health assessment of female elephants in North American zoos and association of husbandry practices with reproductive dysfunction in African Elephants (Loxodonta africana). PLOS ONE 11(7), e0145673.

As part of a multi-institutional study of zoo elephant welfare, we evaluated female elephants managed by zoos accredited by the Association of Zoos and Aquariums and applied epidemiological methods to determine what factors in the...

Meehan, C. L., Hogan, J. N., Bonaparte-Saller, M. K. et al. 2016. Housing and social environments of African (Loxodonta africana) and Asian (Elephas maximus) elephants in North American zoos. PLOS ONE 11(7), e0146703.

We evaluated 255 African (Loxodonta africana) and Asian (Elephas maximus) elephants living in 68 North American zoos over one year to quantify housing and social variables. All parameters were quantified for the both the day...

Coelho, C. M., de Azevedo, C. S., de Barros Vaz Guimarães, M. A. et al. 2016. Environmental enrichment effect on fecal glucocorticoid metabolites and captive maned wolf (Chrysocyon brachyurus) behavior. Journal of Applied Animal Welfare Science 19(4), 353-362.

Environmental enrichment is a technique that may reduce the stress of nonhuman animals in captivity. Stress may interfere with normal behavioral expression and affect cognitive decision making. Noninvasive hormonal studies can provide important information about...

Joyce-Zuniga, N. M., Newberry, R. C., Robbins, C. T. et al. 2016. Positive reinforcement training for blood collection in grizzly bears (Ursus arctos horribilis) results in undetectable elevations in serum cortisol levels: A preliminary investigation. Journal of Applied Animal Welfare Science 19(2), 210-215.

Training nonhuman animals in captivity for participation in routine husbandry procedures is believed to produce a lower stress environment compared with undergoing a general anesthetic event for the same procedure. This hypothesis rests largely on...

Soriano, A. I., Vinyoles, D., Maté, C. 2016. Long-term macroevaluation of environmental enrichment in three brown bears (Ursus arctos) at Barcelona Zoo. Journal of Applied Animal Welfare Science 19(1), 49-61.

The evaluation of enrichment programs is important to determine their effect on nonhuman animal welfare. The daily activity pattern and use of space of 3 brown bears (Ursus arctos) were used for long-term macroevaluation of...

Cortés Duarte, A., Trujillo, F., Superina, M. 2016. Behavioral responses of three armadillo species (Mammalia: Xenarthra) to an environmental enrichment program in Villavicencio, Colombia. Zoo Biology 35(4), 304-312.

Enrichment is a powerful tool to improve the welfare of animals under human care. Stress‐related health and behavioral problems, as well as reproductive failure, are frequent in armadillos (Xenarthra, Cingulata, Dasypodidae) under human care, which...

Bono, L., Mongillo, P., De Boni-Russo, G. et al. 2016. Effects of 2 forms of environmental enrichment on a group of captive blackbucks (Antilope cervicapra): A pilot study. Journal of Veterinary Behavior 12, 66-72.

The aim of this preliminary study was to assess the effects of 2 forms of environmental enrichment (i.e., branched tree trunk and brushes) on the behavior of a group of 8 captive blackbucks. Animals were...

Yamanashi, Y., Matsunaga, M., Shimada, K. et al. 2016. Introducing tool-based feeders to zoo-housed chimpanzees as a cognitive challenge: Spontaneous acquisition of new types of tool use and effects on behaviours and use of space. Journal of Zoo and Aquarium Research 4(3), 147-155.

Cognitively challenging environments are vital to the welfare of captive animals. However, practical enrichment devices that can facilitate animals’ natural behaviours and accommodate individual variation are still limited. We created two types of feeders to...

Ritvo, S. E., MacDonald, S. E. 2016. Music as enrichment for Sumatran orangutans (Pongo abelii). Journal of Zoo and Aquarium Research 4(3), 156-163.

Music is commonly employed as auditory enrichment in NHP facilities under the assumption that music is as enriching for NHPs as it is for humans (Hinds et al., 2007; Lutz & Novak, 2005). The purpose...