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. 
Englund, M. D., Cronin, K. A. 2023. Choice, control, and animal welfare: Definitions and essential inquiries to advance animal welfare science. Frontiers in Veterinary Science 10.

The ways in which humans can support good welfare for animals in their care is an ongoing subject of debate: some place emphasis on the animals’ physical health; others, on animals’ ability to live “natural...

Rogers, L. J. 2023. Knowledge of lateralized brain function can contribute to animal welfare. Frontiers in Veterinary Science 10.

The specialized functions of each hemisphere of the vertebrate brain are summarized together with the current evidence of lateralized behavior in farm and companion animals, as shown by the eye or ear used to attend...

Decker, S., Lavery, J. M., Mason, G. J. 2023. Don’t use it? Don’t lose it! Why active use is not required for stimuli, resources or “enrichments” to have welfare value. Zoo Biology 42(4), 467–475.

Current frameworks for designing and evaluating good enclosures and “enrichments” typically focus on animals’ active interactions with these features. This has undoubtedly improved the welfare of zoo-housed animals over the last 30 years or more...

Tsuchiya, Y., Yayota, M., Kashima, Y. et al. 2023. Nutritional effect of feeding enrichment using bamboo Pleioblastus spp. in zoo-kept Asian elephants Elephas maximus. Journal of Zoo and Aquarium Research 11(2), 267–273.

Many zoos use browse and other roughage as feed ingredients and enrichment tools for elephants. Amongst these are bamboo species (e.g. Pleioblastus spp.), which belong to the family of grasses. Bamboo is used in zoos...

Fernandez, E. J. 2022. Training as enrichment: A critical review. Animal Welfare 31(1), 1-12.

Husbandry training and environmental enrichment are both important advancements associated with current behavioural welfare practices. Additionally, the use of training procedures has been proposed as a form of enrichment, with the implication that training can...

Brereton, J., Rose, P. 2022. An evaluation of the role of 'biological evidence' in zoo and aquarium enrichment practices. Animal Welfare 31(1), 13-26.

Evidence-based approaches are key to advancing all areas of zoo and aquarium practice. Output from empirical study must be disseminated to those within the industry so that results can support changes to husbandry and management...

Vicino, G. A., Sheftel, J. J., Radosevich, L. M. 2022. Enrichment is simple, that’s the problem: Using outcome-based husbandry to shift from enrichment to experience. Animals 12(10), 1293.

Over the decades, the use of environmental enrichment has evolved from a necessary treatment to a “best practice” in virtually all wildlife care settings. The breadth of this evolution has widened to include more complex...

Rose, P. (Ed.) 2022. The Behavioural Biology of Zoo Animals (1st Ed.). CRC Press, Boca Raton, USA. 367 p.

"Zoo animals" as a population are a diverse array of species from all around the globe. When managed in captivity, it is important that key aspects of natural ecology are factored into animal care, as...

Clark, F. E. 2022. Bridging pure cognitive research and cognitive enrichment. Animal Cognition 25(6), 1671–1678.

Cognitive enrichment is a growing subset of environmental enrichment for captive animals. However, it has been difficult for practitioners to design, implement, and evaluate relevant and appropriate cognitive challenges. Even though pure comparative cognition researchers...

Hepps Keeney, C., Harrison, T. M. 2022. Euthanasia complications in non-domestic species. Journal of Zoological and Botanical Gardens 3(4), 616–623.

There are very few studies describing euthanasia complications in non-domestic species. The goal of this study was to survey veterinarians to determine what complications may commonly occur during the euthanasia of non-domestic species. An online...

LaDue, C. A., Schulte, B. A. 2021. Pheromonal enrichment in the zoo: An empirical approach with Asian elephants (Elephas maximus). Applied Animal Behaviour Science 235, 105228.

The use of odors is a popular form of sensory enrichment, yet few studies have investigated the longer lasting effects of biologically relevant chemical signals like pheromones. Asian elephants (Elephas maximus) are unique because they...

Zentall, T. R. 2021. Effect of environmental enrichment on the brain and on learning and cognition by animals. Animals 11(4), 973.

The humane treatment of animals suggests that they should be housed in an environment that is rich in stimulation and allows for varied activities. However, even if one’s main concern is an accurate assessment of...

Hall, B. A., McGill, D. M., Sherwen, S. L. et al. 2021. Cognitive enrichment in practice: A survey of factors affecting its implementation in zoos globally. Animals 11(6), 1721.

Information on the practical use of cognitive enrichment in zoos is scarce. This survey aimed to identify where cognitive enrichment is being used while identifying factors that may limit its implementation and success. Distributed in...

Fernandez, E. J., Upchurch, B., Hawkes, N. C. 2021. Public feeding interactions as enrichment for three zoo-housed elephants. Animals 11(6), 1689.

The past few decades have seen increased interest in studies examining the welfare of elephants and animal–visitor interactions. One understudied area for both pursuits is the impact of public feeding interactions. Our study examined the...

Snowdon, C. T. 2021. Animal signals, music and emotional well-being. Animals 11(9), 2670.

Playing music or natural sounds to animals in human care is thought to have beneficial effects. An analysis of published papers on the use of human-based music with animals demonstrates a variety of different results...

Brown, J. L., Bansiddhi, P., Khonmee, J. et al. 2020. Commonalities in management and husbandry factors important for health and welfare of captive elephants in North America and Thailand. Animals 10(4), 737.

This review paper is a synthesis of results from multiple studies that we have conducted over the past several years using similar methodologies to identify factors related to welfare of captive populations of elephants in...

Williams, E., Carter, A., Hall, C. et al. 2019. Exploring the relationship between personality and social interactions in zoo-housed elephants: Incorporation of keeper expertise. Applied Animal Behaviour Science 221, 104876.

Individual animal personalities affect experiences of zoo environments, and thus potentially welfare. Incorporating keeper knowledge of animal personality in a reliable way has great value in optimising welfare in zoo-housed animals. Assessment of animal personality...

Edwards, K. L., Miller, M. A., Carlstead, K. et al. 2019. Relationships between housing and management factors and clinical health events in elephants in North American zoos. PLOS ONE 14(6), e0217774.

Elephants experience a number of health issues that can contribute to their well-being and survival. In managed populations, housing conditions and management practices can influence individual health, so potential risk factors associated with morbidity or...

Brown, J. L., Carlstead, K., Bray, J. D. et al. 2019. Individual and environmental risk factors associated with fecal glucocorticoid metabolite concentrations in zoo-housed Asian and African elephants. PLOS ONE 14(9), e0217326.

A recent large-scale welfare study in North America involving 106 Asian (Elephas maximus) and 131 African (Loxodonta africana) elephants at 64 accredited facilities identified links (i.e., risk factors) between zoo environmental factors and a number...

Scott, N. L., LaDue, C. A. 2019. The behavioral effects of exhibit size versus complexity in African elephants: A potential solution for smaller spaces. Zoo Biology 38(5), 448-457.

Population-level analyses suggest that habitat complexity, but not necessarily space availability, has important welfare outcomes for elephants in human care. At the Dallas Zoo, the opening of a new exhibit complex allowed us to measure...

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...

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...

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...