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. 
Lambert, H., Elwin, A., D’Cruze, N. 2022. Frog in the well: A review of the scientific literature for evidence of amphibian sentience. Applied Animal Behaviour Science 247, 105559.

Millions of amphibians are traded annually around the world for the exotic pet industry. Their experience during both trade, and in captivity as pets, leads to numerous animal welfare issues. The poor welfare of many...

Schilling, A.-K., Mazzamuto, M. V., Romeo, C. 2022. A review of non-invasive sampling in wildlife disease and health research: What’s new? Animals 12(13), 1719.

In the last decades, wildlife diseases and the health status of animal populations have gained increasing attention from the scientific community as part of a One Health framework. Furthermore, the need for non-invasive sampling methods...

Bernstein‐Kurtycz, L. M., Wiatroski, K. G., Leeds, A. et al. 2022. About pace: How variations in method and definition affect quantification of pacing in bears. Zoo Biology 41(4), 365-372.

Repetitive pacing behavior is exhibited by many species in zoos and is particularly prevalent in carnivores with large home ranges, such as bears. Pacing can be a behavioral indicator of poor welfare, however, understanding this...

Böswald, L. F., Matzek, D., Mohr, H. et al. 2022. Morphometrics of Xenopus laevis kept as laboratory animals. Animals 12(21), 2986.

Morphometric data that provide information on body conditions can be used to monitor the health and well-being of animals. In laboratory animals, they can help to evaluate the stress due to experiments or treatments, following...

Zhang, X., Wang, X., Ayala, J. et al. 2022. Possible effects of early maternal separation on the gut microbiota of captive adult giant pandas. Animals 12(19), 2587.

Maternal deprivation (MD) in early life induces dysbiosis in the host gut microbiota, which is a key determinant of abnormal behavior in stress model individuals. Compared with the early parenting environment of the wild, captive...

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...

Skovlund, C. R., Kirchner, M. K., Moos, L. W. et al. 2021. A critical review of animal-based welfare indicators for polar bears (Ursus maritimus) in zoos: Identification and evidence of validity. Animal Welfare 30(1), 1-18.

Captive polar bears (Ursus maritimus) are well-documented as being prone to behavioural disorders and, as a result, their welfare is the cause of increasing concern. There is therefore a need for an evidence-based approach to...

Fernandez, E. J. 2021. Appetitive search behaviors and stereotypies in polar bears (Ursus maritimus). Behavioural Processes 182, 104299.

Stereotypies in captive animals have been defined as repetitive, largely invariant patterns of behavior that serve no obvious goal or function. Stereotypies are commonly attributed to boredom or stress and are typically treated by enriching...

Coleman, K., Shapiro, S. J. (Eds.). 2021. Behavioral Biology of Laboratory Animals (1st ed). CRC Press, Boca Raton, FL.

This 30-chapter volume informs students and professionals about the behavioral biology of animals commonly housed in laboratory and other captive settings. Each species evolved under specific environmental conditions, resulting in unique behavioral patterns, many of...

Vonk, J., McGuire, M. C., Johnson-Ulrich, Z. 2021. Bearing fruit: Piloting a novel judgment bias task in an American black bear. Zoo Biology 40(2), 89-97.

Judgment bias tasks can reveal changes in affect in animals as a function of environmental manipulations such as provision of enrichment. We assessed affect in an American black bear across seasonal changes in availability of...

Higgins, K., Guerrel, J., Lassiter, E. et al. 2021. Observations on spindly leg syndrome in a captive population of Andinobates geminisae. Zoo Biology 40(4), 330-341.

Amphibian health problems of unknown cause limit the success of the growing number of captive breeding programs. Spindly leg syndrome (SLS) is one such disease, where affected individuals with underdeveloped limbs often require euthanization. We...

Kay, W. R., Mawson, P. R. 2021. An efficient method for the euthanasia of cane toads (Rhinella marina) under northern Australian field conditions. Animals 11(8), 2239.

The euthanasia of cane toads under field conditions presents a number of logistical and animal welfare challenges. One recommended method of control involves the use of carbon dioxide in plastic bags. This paper describes the...

Maher, C. J., Gibson, A., Dixon, L. M. et al. 2021. Developing a reliable welfare assessment tool for captive hibernatory bear species. Animals 11(11), 3090.

Animal welfare assessments are essential for the identification of welfare hazards and benchmarking of welfare improvements, though welfare assessments for zoo species are lacking. Bears are commonly housed in zoos but currently no composite welfare...

Zemanova, M. A. 2021. Noninvasive genetic assessment is an effective wildlife research tool when compared with other approaches. Genes 12(11), 1672.

Wildlife research has been indispensable for increasing our insight into ecosystem functioning as well as for designing effective conservation measures under the currently high rates of biodiversity loss. Genetic and genomic analyses might be able...

Hausmann, J. C., Krisp, A. R., Mans, C. et al. 2021. Analgesic efficacy of tramadol and morphine in White's tree frogs (Litoria caerulea). JAALAS 60(6), 681-686.

Published data are sparse regarding the recognition of clinically relevant pain and appropriate analgesia in amphibians. The amphibian analgesia literature has primarily focused on nociceptive pathways in a single species, the northern leopard frog (Rana...

Monreal-Pawlowsky, T., Vaicekauskaitė , R., Palencia Membrive, G. et al. 2021. Goal-oriented behavioural and environmental enrichment in aquarium species. Journal of Zoo and Aquarium Research, 9(4), 273-280.

Environmental enrichment is a common tool used in zoo and aquarium settings to provide mental and physical stimulation to animals under human care. This paper aims to present a primary approach to goal-oriented environmental and...

Ramos, J., Ortiz-Díez, G. 2021. Evaluation of environmental enrichment for Xenopus laevis using a preference test. Laboratory Animals 55(5), 428-434.

Xenopus laevis frogs have long been widely used as an animal model in research. However, their husbandry has scarcely evolved, although they are prone to environmental stress. Environmental enrichment has been shown to improve animal...

Bernstein-Kurtycz, L. M., Koester, D. C., Snyder, R. J. et al. 2021. “Bearly” changing with the seasons: Bears of five species show few behavioral changes across seasons and at varying visitor densities. Animal Behavior and Cognition 8(4), 538–557.

In natural environments, bear behavior follows seasonal patterns but the zoo environment differs from the natural environment in several ways, including the presence of zoo visitors. Although typically difficult to disentangle, we were able to...

Fuller, G., Hamilton, J., Allard, S. 2021. DNA damage as a potential non-invasive indicator of welfare: A preliminary study in zoo-housed grizzly bears (Ursus arctos horribilis). Journal of Zoological and Botanical Gardens 2(3), 316–334.

Measures of oxidative stress have potential for integrating positive and negative life experiences into comprehensive cellular indicators of animal welfare. We explored this possibility when three adult grizzly bear brothers at the Detroit Zoo were...

Woody, S. M., Santymire, R. M., Cronin, K. A. 2021. Posture as a non-invasive indicator of arousal in American toads (Anaxyrus americanus). Journal of Zoological and Botanical Gardens 2(1), 1–9.

Animal welfare has become a priority for modern zoos and aquariums. However, amphibians have not yet been the focus of much welfare research, perhaps in part because they do not tend to display many quantifiable...

Melfi, V. A., Dorey, N. R., Ward, S. (Eds.) 2020. Zoo Animal Learning and Training. John Wiley & Sons: Hoboken, NJ, 384 pp.

Comprehensively explains animal learning theories and current best practices in animal training within zoos. This accessible, up-to-date book on animal training in a zoo/aquaria context provides a unified approach to zoo animal learning, bringing together...

Harvey, A., Beausoleil, N., Ramp, D. et al. 2020. A ten-stage protocol for assessing the welfare of individual non-captive wild animals: Free-roaming horses (Equus ferus caballus) as an example. Animals 10(1), 148.

Knowledge of the welfare status of wild animals is vital for informing debates about the ways in which we interact with wild animals and their habitats. Currently, there is no published information about how to...

Zemanova, M. A. 2020. Towards more compassionate wildlife research through the 3Rs principles: Moving from invasive to noninvasive methods. Wildlife Biology 2020(1), no page numbers.

Research in ecology and wildlife biology remains crucial for increasing our knowledge and improving species management and conservation in the midst of the current biodiversity crisis. However, obtaining information on population status often involves invasive...

Hammond, C. 2020. Comparing the frequency of stereotypical and non-stereotypical behaviours in captive brown bears (Ursus arctos arctos) at The Wildwood Trust. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 47(1), 4-7.

Zoos play an important role in conservation, participating in captive breeding programmes and scientific research. The research can be shared and inform practice in the field and zoos. A behavioural observation study was conducted on...

Galex, I. A., Gallant, C. M., D'Avignon, N. et al. 2020. Evaluation of effective and practical euthanasia methods for larval African clawed frogs (Xenopus laevis). JAALAS 59(3), 269–274.

Larval, or tadpole-stage Xenopus laevis frogs are a popular research model for developmental biology and disease studies. Existing euthanasia guidance documents offer recommendations for both eggs and adult stages, yet do not specifically address the...