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. 
Brooks, J., Yoshimura, H., Taki, Y. 2021. Knowledge-based enrichment: Development of a novel enrichment device for captive chimpanzees. Zoo Biology 40(5), 398-406.

The field of environmental enrichment has grown considerably, but most enrichment is still focused on tasks where highly valued food rewards are directly visible. We designed a device which would instead make use of knowledge...

Serres, A., Hao, Y., Wang, D. 2020. Swimming features in captive odontocetes: Indicative of animals’ emotional state? Behavioural Processes 170, 103998.

Captive welfare studies in odontocete species have been mostly conducted on bottlenose dolphins (Tursiops truncatus) while the welfare of many other species’ -including endangered species- remains poorly studied. More research is needed to find and...

Matsuzawa, T. 2020. WISH cages: Constructing multiple habitats for captive chimpanzees. Primates 61(2), 139–148.

This article aims to introduce environmental enrichment for captive chimpanzees in Japan in a historical context. It describes the most recent endeavor of constructing huge cages and connecting multiple habitats. The Ai Project, a series...

Inoue, N., Shimada, M. 2020. Comparisons of activity budgets, interactions, and social structures in captive and wild chimpanzees (Pan troglodytes). Animals 10(6), 1063.

Chimpanzees in zoos with sufficient and appropriate environmental enrichment devices are expected to exhibit behaviors, interactions, and societies similar to those in the wild. In this study, we compared the activity budgets of each observed...

Buchanan, K. 2020. DIY: Foraging balls. Laboratory Animal Science Professional 8(3) (May/June), 51.

This article describes the steps for making a DIY guinea pig or rabbit cardboard foraging ball. Pictures are provided for each step as well as the completed ball. These cardboard foraging balls can be made...

Mendonça Soares, S., Kirsten, K., Pompermaier, A. et al. 2020. Sex segregation affects exploratory and social behaviors of zebrafish according to controlled housing conditions. Physiology & Behavior 222, 112944.

Zebrafish has become an animal model in research and articles have established ideal conditions for their maintenance. However, little is known regarding the influence of gender and other cues on zebrafish behavior. Thus, here we...

Matrai, E., Ng, A. K. W., Chan, M. M. H. et al. 2020. Testing use of a potential cognitive enrichment device by an Indo‐Pacific bottlenose dolphin (Tursiops aduncus). Zoo Biology 39(3), 156–167.

Cognitive enrichment aims to provide animals with opportunities to use their cognitive skills and to promote behaviors associated with positive wellbeing. Cooperation in mammals has been recorded during various behavioral contexts such as hunting, mating...

Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...

Lauderdale, L. K., Miller, L. J. 2020. Efficacy of an interactive apparatus as environmental enrichment for common bottlenose dolphins (Tursiops truncatus). Animal Welfare 29(4), 379-386.

Environmental enrichment is a key component in improving the psychological and physiological well-being of animals under professional care. Environmental enrichment involves the addition of stimuli, including objects and cognitive challenges, into the environment in order...

Krueger, L. D., Thurston, S. E., Kirk, J. et al. 2020. Enrichment preferences of singly housed zebrafish (Danio rerio). JAALAS 59(2), 148–155.

Despite the increasing popularity of zebrafish (Danio rerio) as an animal model, the environmental enrichment preferences of this species have been largely unexplored. We sought to determine the preferences of mature female zebrafish that were...

Worlds, T., Kearney, M., De La Garza, F. et al. 2020. Development of a rabbit enrichment program and contribution to a culture of transparency and care. Laboratory Animal Science Professional 8(6) (November/December), 38-40.

The Becton Dickinson (BD) Research Animal Care Program has developed an acclimation and enrichment program that has enhanced animal welfare for studies requiring single housing, contributed to a culture of care, increased transparency, and improved...

Yamanashi, Y., Bando, H., Matsunaga, M. et al. 2020. Development of bed-building behaviors in captive chimpanzees (Pan troglodytes): Implication for critical period hypothesis and captive management. Primates 61(5), 639-646.

Wild great apes build beds for sleeping by combining tree branches or other vegetation, but the development of this behavior is poorly understood. We investigated the development of bed-building behaviors by conducting complementary cross-sectional and...

McMahon, S. A., Wigham, E. 2020. ‘All Ears’: A questionnaire of 1516 owner perceptions of the mental abilities of pet rabbits, subsequent resource provision, and the effect on welfare. Animals 10(10), 1730.

Pet rabbit welfare is a hidden crisis: Inappropriately housed, fed, and not routinely provided healthcare—rabbits can often suffer painful conditions and shortened lifespans. This study provides novel understanding of owners’ perceptions of rabbits’ mental capabilities...

Coda, K. A., Fortman, J. D., García, K. D. 2020. Behavioral effects of cage size and environmental enrichment in New Zealand white rabbits. JAALAS 59(4), 356-364.

One of the goals of environmental enrichment is to encourage species-typical behaviors, while discouraging abnormal behaviors or stereotypies. Assessing the effectiveness of various enrichment modalities can be challenging, particularly for prey species such as rabbits...

Boesch, C. 2020. Mothers, environment, and ontogeny affect cognition. Animal Behavior and Cognition 7(3), 474–489.

The book “Folk Physics for Apes” remains a fascinating book about the way one captive peer-group of chimpanzees understand the world in which they grew. However, the very special living conditions these seven individuals faced...

Tan, S. L. T., Handasyde, K. A., Rault, J.-L. et al. 2020. Insensitivity to reward shifts in zebrafish (Danio rerio) and implications for assessing affective states. Animal Cognition 23(1), 87–100

Theory and empirical findings predict that individuals in a negative affective state are more sensitive to unexpected reward loss and less sensitive to unexpected reward gain compared to individuals in a neutral or positive affective...

Arechavala-Lopez, P., Saraiva, J. L. 2019. Welfare of Cultured and Experimental Fishes. Basel, Switzerland: MDPI, 132 pages.

This open access book is a printed edition of the Special Issue on Welfare of Cultured and Experimental Fishes that was published in the journal Fishes. The PDF is free for download.

Woodward, M. A., Winder, L. A., Watt, P. J. 2019. Enrichment increases aggression in zebrafish. Fishes 4(1), 22.

Environmental enrichment, or the enhancement of an animal’s surroundings when in captivity to maximise its wellbeing, has been increasingly applied to fish species, particularly those used commercially. Laboratory species could also benefit from enrichment, but...

Mastellone, V., Bovera, F., Musco, N. et al. 2019. Mirrors improve rabbit natural behavior in a free-range breeding system. Animals 9(8), 533.

The aim of this research was to evaluate the possible usefulness of mirrors in improving rabbit behavior in a free-range breeding system. Three groups (each consisting of nine replicates of three animals) were compared: isolated...

Trocino, A., Zomeño, C., Filiou, E. et al. 2019. The use of environmental enrichments affects performance and behavior of growing rabbits housed in collective pens. Animals 9(8), 537.

This study assessed the effects of an elevated plastic-slatted platform and/or a plastic hiding tube in collective pens with large group sizes (27 or 36 rabbits/pen; 16 rabbits/m2) on the performance and welfare of rabbits...

DePasquale, C., Fettrow, S., Sturgill, J. et al. 2019. The impact of flow and physical enrichment on preferences in zebrafish. Applied Animal Behaviour Science 215, 77-81.

Environmental enrichment is used extensively to improve the welfare of animals in captivity, however, the importance of physical exercise as enrichment is only now coming to light. A key question in assessing the welfare of...

Bloomsmith, M. A., Clay, A. W., Lambeth, S. P. et al. 2019. Survey of behavioral indices of welfare in research chimpanzees (Pan troglodytes) in the United States. JAALAS 58(2), 160-177.

Chimpanzees demand specialized housing and care and the highest degree of attention to animal welfare. The current project used a survey method to collate information on chimpanzee housing and behavioral indices of welfare across all...

Lee, C. J., Paull, G. C., Tyler, C. R. 2019. Effects of environmental enrichment on survivorship, growth, sex ratio and behaviour in laboratory maintained zebrafish Danio rerio. Journal of Fish Biology 94(1), 86-95.

Environmental enrichment involves increasing the complexity of a fish's environment in order to improve welfare. Researchers are legally obliged to consider the welfare of laboratory animals and poor welfare may result in less robust data...

Jones, N. A. R., Spence, R., Jones, F. A. M. et al. 2019. Shade as enrichment: Testing preferences for shelter in two model fish species. Journal of Fish Biology 95(4), 1161-1165.

We compared preferences shown by zebrafish (Danio rerio) and three-spined stickleback (Gasterosteus aculeatus) for shelter provided by above-tank shade and artificial plants. Zebrafish showed no preference for either shelter, whereas sticklebacks showed a preference for...

Animal Welfare Institute. 2019. Let’s get serious about animal play. AWI Quarterly 68(3) Fall, 19.

This article describes the importance of providing laboratory animals with opportunities to engage in play, and provides a few practical ideas for how to do this.