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. 
Bissonnette, P. B., Waterman, J. M., Petersen, S. D. 2023. The use of infrared thermography to noninvasively measure the surface temperature of polar bears during bouts of social play. Zoo Biology 42(1), 38–44.

Infrared thermography or thermal imagery is a noninvasive tool that can be used to measure the temperature of surfaces. Typically, thermal imagery is used for construction or military purposes but is increasingly used as a...

Broche, N., Mouri, K., Suzumura, T. et al. 2023. Measuring short-term changes in stress-associated salivary analytes in free-ranging Japanese macaques (Macaca fuscata). Primates 64(4), 439–449.

Monitoring short-term changes of endocrine responses in non-human primates living in wild populations is a challenge. Saliva contains enzymes, steroids, and various analytes that can be broadly useful for helping us understand physiological responses to...

Cambrelen, D., Nelson Slater, M. 2023. Case study: Modifying repetitive behavior in a polar bear (Ursus maritimus). Zoo Biology 42(3), 390–396.

Stereotypic pacing in zoo-housed carnivores has been intensively researched for decades, revealing that it is a subtly complex behavior with a highly variable etiology. While pacing can be an indicator of poor welfare, it can...

Ghavamian, Y., Minier, D. E., Jaffe, K. E. 2023. Effects of complex feeding enrichment on the behavior of captive Malayan sun bears (Helarctos malayanus). Journal of Applied Animal Welfare Science 26(4), 670–684.

All zoos grapple with challenges of keeping captive animals engaged in natural behaviors, especially for bears which prove to be among the more challenging species to keep stimulated. In captivity, a common indicator of poor...

Haertel, A. J., Beisner, B. A., Buehler, M. S. et al. 2023. The impact of housing on birth outcomes in breeding macaque groups across multiple research centers. American Journal of Primatology 85(11), e23554.

Demand for nonhuman primates in research has increased over the past several years, while nonhuman primate supply remains a challenge in the United States. Global nonhuman primate supply issues make it increasingly important to maximize...

Hanh, H. Q., Phuong, N. T., Tien, N. D. et al. 2023. Effects of stocking density in group cages on egg production, profitability, and aggressive pecking of hens. Journal of Applied Animal Welfare Science 26(3), 374–385.

There is an increasing concern about welfare issues related to battery cages, which are commonly used in Vietnam, and requires a modified cage that improves hen welfare while retaining its economic and management advantages. We...

Kleinlugtenbelt, C., Clauss, M., Burkevica, A. et al. 2023. Fasted and furious? Considerations on the use of fasting days in large carnivore husbandry. Journal of Zoo and Aquarium Research 11(3), 318–323.

Many large mammalian terrestrial carnivores do not hunt every day in their natural habitats, because given the right prey, they can gorge-feed more than their daily energy and nutrient requirements. At the same time, there...

Oke, O. E., Oso, O., Iyasere, O. et al. 2023. Evaluation of light color manipulation on behavior and welfare of broiler chickens. Journal of Applied Animal Welfare Science 26(4), 493–504.

This experiment evaluated the effect of light manipulation on the behavior and welfare of broilers using 280-day-old Arbor-Acre chicks, which were weighed and assigned to 7 treatments having 4 replicates and 10 birds per replicate...

Psarou, E., Vezoli, J., Schölvinck, M. L. et al. 2023. Modular, cement-free, customized headpost and connector-chamber implants for macaques. Journal of Neuroscience Methods 393, 109899.

Background: Neurophysiological studies with awake macaques typically require chronic cranial implants. Headpost and connector-chamber implants are used to allow head stabilization and to house connectors of chronically implanted electrodes, respectively. New method: We present long-lasting...

de Oliveira sans, E. C., Dahlke, F., Freitas Federici, J. et al. 2023. Welfare of broiler chickens in Brazilian free-range versus intensive indoor production systems. Journal of Applied Animal Welfare Science 26(4), 505–517.

We compared broiler chicken welfare in free-range (FR) and intensive indoor (IN) systems using the Welfare Quality® Protocol. Ten FR and 11 IN farms in Brazil were assessed. Results are shown as either scores ranging...

Zhao, S., Zhang, R., Li, C. et al. 2023. The effect of short-term classical music stimulus on behavior and tonic immobility reaction of pullets. Journal of Applied Animal Welfare Science 26(3), 386–392.

The purpose of this study was to investigate the effect of short-term stimulation of classical music on the behavior of pullets and to explore whether classical music as an auditory enrichment factor reduces the fear...

Sharma, S., Khanal, L., Shrestha, S. et al. 2023. Zoo visitors as a source of enrichment to reduce abnormal behavior in captive rhesus macaques (Macaca mulatta) in the Central Zoo, Kathmandu, Nepal. Journal of Animal Behaviour Biometeorology 11(1), e2023005.

Overexpression of abnormal behavior among captive primates indicates poor management practices. The type, frequency, and contributing factors of abnormal behaviors vary highly across individual animals in captive settings. This study explored if sex, rearing history...

LaFollette, M. R., Cloutier, S., Brady, C. M. et al. 2023. Benchmarking enrichment efforts in the US & Canada across species and enrichment categories. JAALAS 62(4), 303–316.

Enrichment is important for animal welfare and data quality. Provision of enrichment opportunities varies between species and enrichment category. However, data benchmarking these differences does not exist. Our objective was to characterize enrichment provision and...

Allworthy, S. 2023. Inspired by ABWAK – Making a red panda mirror box. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 50(1), 15.

I've been lucky enough to work with red pandas for around eight years now and during that time worked on a training plan for health checks, routine weighing and general husbandry. Through this training program...

Vize, E., Westwood, C., Garner, P. 2023. Bamboo preference in a pair of captive red panda, Ailurus fulgens. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 50(2), 4-5.

For this study, two female red pandas, Pema and Tika, were observed. They are twin sisters and were both six years old at the time of the study. Observations were conducted over twelve days.This study...

Paul, E. S., Browne, W., Mendl, M. T. et al. 2022. Assessing animal welfare: A triangulation of preference, judgement bias and other candidate welfare indicators. Animal Behaviour 186, 151-177.

To assess the welfare of captive animals, validated measures, so-called ‘welfare indicators’, are required. We used a triangulation approach to investigate the extent to which different measures converged to provide corroborating evidence of welfare. Laying...

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...

Rana, M. S., Lee, C., Lea, J. M. et al. 2022. Commercial free-range laying hens’ preferences for shelters with different sunlight filtering percentages. Animals 12(3), 344.

Extreme sunlight might be aversive to free-range laying hens, discouraging them from going outside. Range enrichment with artificial shelters may protect hens from sunlight and increase range use. The preferences of 34–40-week-old Hy-Line Brown laying...

Taylor, P. S., Hemsworth, P. H., Rault, J.-L. 2022. Environmental complexity: Additional human visual contact reduced meat chickens’ fear of humans and physical items altered pecking behavior. Animals 12(3), 310.

Increased environmental complexity can improve animal welfare, depending on the resources provided and use by the animal. We provided chickens either with physical items that posed no biosecurity risk and were inexpensive (balls, chains, perches...

Campbell, D. L. M., Belson, S., Dyall, T. R. et al. 2022. Impacts of rearing enrichments on pullets’ and free-range hens’ positive behaviors across the flock cycle. Animals 12(3), 280.

Enrichment during the indoor rearing of pullets destined for free-range systems may optimize pullet development including increasing motivated natural behaviors (termed ‘positive behaviors’) including foraging, dust bathing and chick play. Hy-Line Brown® chicks (n =...

Acharya, R. Y., Hemsworth, P. H., Coleman, G. J. et al. 2022. The animal-human interface in farm animal production: Animal fear, stress, reproduction and welfare. Animals 12(4), 487.

A negative human-animal relationship (HAR) from the perspective of the animal is a limiting factor affecting farm animal welfare, as well as farm animal productivity. Research in farm animals has elucidated sequential relationships between stockperson...

Rowe, E., Mullan, S. 2022. Advancing a “good life” for farm animals: Development of resource tier frameworks for on-farm assessment of positive welfare for beef cattle, broiler chicken and pigs. Animals 12(5), 565.

There is increasing recognition that farm animal welfare standards should ensure positive welfare, as well as prevent negative welfare. Resources that are valued by an animal and that provide opportunities to engage in motivated behaviours...

Mocz, F., Michel, V., Janvrot, M. et al. 2022. Positive effects of elevated platforms and straw bales on the welfare of fast-growing broiler chickens reared at two different stocking densities. Animals 12(5), 542.

In conventional rearing systems, fast-growing broiler chickens commonly experience welfare issues, such as contact dermatitis, walking difficulties or a lack of expression of species-specific behaviours. Enriching their environment may be a way to improve their...

Zuerl, M., Stoll, P., Brehm, I. et al. 2022. Automated video-based analysis framework for behavior monitoring of individual animals in zoos using deep learning—A study on polar bears. Animals 12(6), 692.

The monitoring of animals under human care is a crucial tool for biologists and zookeepers to keep track of the animals’ physical and psychological health. Additionally, it enables the analysis of observed behavioral changes and...

Baker, P. E., Nicol, C. J., Weeks, C. A. 2022. The effect of hard pecking enrichment during rear on feather cover, feather pecking behaviour and beak length in beak-trimmed and intact-beak laying hen pullets. Animals 12(6), 674.

Injurious pecking, commonly controlled by beak trimming (BT), is a widespread issue in laying hens associated with thwarted foraging. This controlled study compared the effect in intact and beak-trimmed pullets of providing pecking pans to...