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. 
Funkhouser, J. A., Mayhew, J. A., Mulcahy, J. et al. 2021. Human caregivers are integrated social partners for captive chimpanzees. Primates 62(2), 297–309.

In a captive environment, it is challenging to ensure the highest level of social and psychological well-being for species with naturally complex social organizations and structures. There is a growing need to meet the social...

Vaglio, S., Kaburu, S. S. K., Pearce, R. et al. 2021. Effects of scent enrichment on behavioural and physiological indicators of stress in zoo primates. American Journal of Primatology 83(5), e23247.

Captive breeding is vital for primate conservation, with modern zoos serving a crucial role in breeding populations of threatened species and educating the general public. However, captive populations can experience welfare issues that may also...

Spiezio C., Vaglio, S., Vandelle C. et al. 2021. Effects of rearing on the behaviour of zoo-housed chimpanzees (Pan troglodytes). Folia Primatologica 92(2), 91–102.

Early-life experiences may considerably affect the behavioural patterns of adult primates. Particularly, atypical rearing practices might lead to abnormal behaviours and social-sexual deficiencies in captive, adult non-human primates. We conducted behavioural observations of mother-reared (n...

Lambert, K. 2021. DIY: Acacia gum sealed paper straws. Laboratory Animal Science Professional 9(3) (May/June), 37.

This DIY snack is great for NHP and can be customized in a variety of ways.

Carter, M., Sherwen, S., Webber, S. 2021. An evaluation of interactive projections as digital enrichment for orangutans. Zoo Biology 40(2), 107-114.

Digital technologies are increasingly being incorporated into the provision of enrichment for captive primates, ranging from the ad-hoc use of iPads to specifically designed hardware installed in the design of new exhibits. In this article...

Hall, K., Bryant, J., Staley, M. et al. 2021. Behavioural diversity as a potential welfare indicator for professionally managed chimpanzees (Pan troglodytes): Exploring variations in calculating diversity using species-specific behaviours. Animal Welfare 30(4), 381-392.

Behavioural diversity may serve as a positive indicator of animal welfare that can be applied in long-term monitoring schemes in managed settings (eg zoos, laboratories, farms). Behavioural diversity is often higher when animals live in...

Travain, T., Valsecchi, P. 2021. Infrared thermography in the study of animals’ emotional responses: A critical review. Animals 11(9), 2510.

Whether animals have emotions was historically a long-lasting question but, today, nobody disputes that they do. However, how to assess them and how to guarantee animals their welfare have become important research topics in the...

Padrell, M., Amici, F., Córdoba, M. P. et al. 2021. Artificial termite-fishing tasks as enrichment for sanctuary-housed chimpanzees: Behavioral effects and impact on welfare. Animals 11(10), 2941.

Artificial termite-fishing tasks are a common enrichment for captive great apes, promoting species-typical behaviors. Nonetheless, whether these activities are linked to changes in other behaviors and whether these changes persist over time has seldom been...

Diana, A., Salas, M., Pereboom, Z. et al. 2021. A systematic review of the use of technology to monitor welfare in zoo animals: Is there space for improvement? Animals 11(11), 3048.

A top priority of modern zoos is to ensure good animal welfare (AW), thus, efforts towards improving AW monitoring are increasing. Welfare assessments are performed through more traditional approaches by employing direct observations and time-consuming...

Lambert, K. 2021. DIY: Acacia gum hanging saucer. Laboratory Animal Science Professional 9(5) (September/October), 50.

This article describes the ingredients, supplies, and directions to make this DIY hanging item, which is great for NHP and swine.

Lambert, K. 2021. DIY: Busy boxes. Laboratory Animal Science Professional 9(6) (November/December), 32.

This article describes the ingredients and directions to make this simple DIY destructible enrichment for NHP and swine.

Ross, S. R., Lake, B. R., Fultz, A. et al. 2021. An evaluation of thermal imaging as a welfare monitoring tool for captive chimpanzees. Primates 62(6), 919-927.

Among the growing list of novel tools with which to assess animal welfare is the use of thermal (infrared) imaging. The technology has already been utilized to identify emotional arousal in several nonhuman primate species...

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...

Nash, R., Johnston, H., Robbins, A. et al. 2021. The effect of enrichment filling and engagement time on regurgitation and reingestion behaviour in three zoo-housed orangutans. Journal of Zoological and Botanical Gardens 2(1), 10–20.

Regurgitation and reingestion (R/R) is a prevalent, abnormal behaviour observed in captive great apes. R/R may be related to animal welfare and while less R/R appears to occur when apes are provided with browse and...

Crailsheim, D., Stüger, H., P., Kalcher-Sommersguter, E. et al. 2020. Early life experience and alterations of group composition shape the social grooming networks of former pet and entertainment chimpanzees (Pan troglodytes). PLOS ONE 15(1), e0226947.

The long-term effects of early life adversities on social capacities have been documented in humans and wild-caught former laboratory chimpanzees (Pan troglodytes). However, former pet and entertainment chimpanzees have received little attention to date. This...

Ross, S. R., Leinwand, J. G. 2020. A review of research in primate sanctuaries. Biology Letters 16(4), 1620200033.

While non-human primate studies have long been conducted in laboratories, and more recently at zoological parks, sanctuaries are increasingly considered a viable setting for research. Accredited sanctuaries in non-range countries house thousands of primates formerly...

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...

Ebel, S. J., Kopp, K. S., Liebal, K. 2020. Object preferences in captive Sumatran orang-utans (Pongo abelii). Behavioural Processes 170, 103993.

While preferences for perceptual features of objects are well studied in humans, little is known about this trait in other great apes. We therefore presented captive Sumatran orang-utans (Pongo abelii) with objects that differed in...

Earl, S. C., Hopper, L. M., Ross, S. R. 2020. Same space, different species: The influence of exhibit design on the expression of zoo-housed apes’ species-typical retiring behaviors. Animals 10(5), 836.

Wild chimpanzees frequently make arboreal nests, while wild lowland gorillas typically nest on the ground. We aimed to understand whether zoo-housed apes’ use of elevated spaces for retiring similarly differed between species and across exhibits...

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...

Allanic, M., Hayashi, M., Matsuzawa, T., 2020. Investigating the function of mutual grooming in captive bonobos (Pan paniscus) and Chimpanzees (Pan troglodytes). Folia Primatologica 91, 481-494.

Social grooming is often exchanged between individuals in many primate species. Rates of bidirectional (or simultaneous mutual) grooming vary across primate species, and its function is not yet fully understood. For example, mutual grooming is...

Cloutier Barbour, C., Danforth, M. D., Murphy, H. et al. 2020. Monitoring great ape heart health through innovative electrocardiogram technology: Training methodologies and welfare implications. Zoo Biology 39(6), 443-447.

Assessing and treating cardiovascular disease (or heart disease) is a growing concern for institutions housing great apes, as it is a major cause of mortality in all four taxa managed in human care. As part...

Reamer, L. A., Neal Webb, S. J., Jones, R. et al. 2020. Validation and utility of a body condition scoring system for chimpanzees (Pan troglodytes). American Journal of Primatology 82(10), e23188.

Obesity is a problem in captive chimpanzee colonies that can lead to increased risk for disease; therefore, implementation of effective weight management strategies is imperative. To properly implement a weight management program, captive managers should...

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...

Perea Garcia, J. O., Miani, A., Kristian Olsen Alstrup, A. et al. 2020. Orangulas: Effect of scheduled visual enrichment on behavioral and endocrine aspects of a captive orangutan (Pongo pygmaeus): Effect of scheduled visual enrichment on behavioral and endocrine aspects of a captive orangutan. Journal of Zoo and Aquarium Research, 8(1), 67-72.

Captivity may have adverse effects on captive great apes, who would spend much more of their time engaged in foraging and other activities in the wild. Enrichment interventions have the potential to alleviate the adverse...