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. 
Robinson, L. M., Weiss, A. (Eds.) 2023. Nonhuman Primate Welfare: From History, Science, and Ethics to Practice. Springer, Cham, Switzerland. 671 p.

This volume reviews the broad topic of welfare in nonhuman primates under human care. Chapters detail the history of primates in captivity, ethical and legal issues surrounding the use of nonhuman primates as entertainment or...

Pallieres, C. G. D., Rose, P. E. 2023. Two’s company, three species is a crowd? A webcam-based study of the behavioural effects of mixed-species groupings in the wild and in the zoo. PLOS ONE 18(4), e0284221.

Mixed species exhibits in zoos are used to create larger, more stimulating environments to support naturalistic interactions between species. In the wild, mixed species groups are observed as having lower rates of vigilance, presumably due...

Clark, F. E. 2023. In the zone: Towards a comparative study of flow state in primates. Animal Behavior and Cognition 10(1), 62–88.

Flow is an altered state of feeling ‘in the zone’ when fully absorbed in a challenge and is associated with positive affective state (feelings). Despite almost five decades of research, Flow has not yet been...

Schreier, A. L., Readyhough, T. S., Moresco, A. et al. 2023. Social dynamics of a newly integrated bachelor group of Asian elephants (Elephas maximus): Welfare implications. Journal of Applied Animal Welfare Science 26(2), 229–246.

Male associations are a typical component of elephant society, allowing bulls to practice appropriate social behavior. To improve zoo elephant welfare, it is important to provide bulls with social opportunities. In fall 2018, Denver Zoo...

Orient, E., Guillén‐Salazar, F. 2022. Evaluation of social compatibility in an all‐male group of chimpanzees (Pan troglodytes) by means of social network analysis. Zoo Biology 41(1), 84-93.

The study here presented provides preliminary data regarding social compatibility of an all-male group of five chimpanzees (Pan troglodytes), assessed by means of a social network analysis (SNA). The study was conducted at the Fundació...

Fultz, A., Yanagi, A., Breaux, S. et al. 2022. Aggressive, submissive, and affiliative behavior in sanctuary chimpanzees (Pan Troglodytes) during social integration. Animals 12(18), 2421.

Chimp Haven is a sanctuary for chimpanzees being retired from biomedical research and from facilities that can no longer care for them. Chimpanzees often live in smaller groups in captive settings; however, Chimp Haven integrates...

Escribano, D., Doldán-Martelli, V., Cronin, K. A. et al. 2022. Chimpanzees organize their social relationships like humans. Scientific Reports 12(1), 16641.

Human relationships are structured in a set of layers, ordered from higher (intimate relationships) to lower (acquaintances) emotional and cognitive intensity. This structure arises from the limits of our cognitive capacity and the different amounts...

Readyhough, T. S., Joseph, S., Davis, M. et al. 2022. Impacts of socialization on bull Asian elephant (Elephas maximus) stereotypical behavior. Journal of Zoological and Botanical Gardens 3(1), 113–130.

There is a growing need for animal care institutions to house multiple bull elephants as the population increases due to transfers from private ownership and the births of male offspring in managed care. Elephants in...

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...

Lasky, M., Campbell, J., Osborne, J. A. et al. 2021. Increasing browse and social complexity can improve zoo elephant welfare. Zoo Biology 40(1), 9–19.

While recent work has assessed how environmental and managerial changes influence elephant welfare across multiple zoos, few studies have addressed the effects of management changes within a single institution. In this paper, we examine how...

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...

Hörner, F., Oerke, A.-K., Müller, D. W. H. et al. 2021. Monitoring behaviour in African elephants during introduction into a new group: Differences between related and unrelated animals. Animals 11(10), 2990.

The introduction of elephants into new groups is necessary for breeding programmes. However, behavioural studies on the reactions of these animals at first encounters are missing. In the present study, female African elephants (Loxodonta africana)...

da Silva Medeiros Elidio, H., Coelho, J. W. R., Cavalcanti Pereira da Silva, L. C. et al. 2021. Housing density and aggression in Syrian hamsters. JAALAS 60(5), 506-509.

The Syrian hamster (Mesocricetus auratus) is a solitary and naturally territorial animal, with female hamsters being more aggressive than males. This behavior makes handling difficult because they are usually housed in groups, which can lead...

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...

Goldsborough, Z., van Leeuwen, E. J. C., Kolff, K. W. T. et al. 2020. Do chimpanzees (Pan troglodytes) console a bereaved mother? Primates volume 61(1), 93–102.

Comparative thanatology encompasses the study of death-related responses in non-human animals and aspires to elucidate the evolutionary origins of human behavior in the context of death. Many reports have revealed that humans are not the...

Sharma, N., Sharma Pokharel, S., Kohshima S. et al. 2020. Behavioural responses of free-ranging Asian elephants (Elephas maximus) towards dying and dead conspecifics. Primates 61(1), 129–138.

Reactions to dying and dead conspecifics have been observed in many non-human animals. Elephants, particularly African elephants, are thought to have an awareness of the death of their conspecifics, as they show compassionate behaviour towards...

Veasey, J. 2020. Assessing the psychological priorities for optimising captive Asian elephant (Elephas maximus) welfare. Animals 10(1), 39.

The welfare status of elephants under human care has been a contentious issue for two decades or more in numerous western countries. Much effort has gone into assessing the welfare of captive elephants at individual...

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...

Evison, E., McKenzie, A., Holmes, L. 2020. Social and environmental impacts on sleep in captive Asian elephants (Elephas maximus). Zoo Biology 39(6), 397-404.

Modern zoos strive to improve standards of animal management, husbandry and welfare of their animals as part of a continual evaluation process. Elephants (Elephantidae) have received particular attention in recent years due to the challenge...

Glaeser, S. S., Edwards, K. L., Wielebnowski, N. et al. 2020. Effects of physiological changes and social life events on adrenal glucocorticoid activity in female zoo-housed Asian elephants (Elephas maximus). PLOS ONE 15(11), e0241910.

Ensuring good health and welfare is an increasingly important consideration for conservation of endangered species and includes breeding of individuals managed under human care. Understanding how factors in the captive environment affect individual animal wellbeing...

Borland, J. M., Kim, E., Swanson, S. P. et al. 2020. Effect of aggressive experience in female Syrian hamsters on glutamate receptor expression in the nucleus accumbens. Frontiers in Behavioral Neuroscience 14, 583395.

Our social relationships determine our health and well-being. In rodent models, there is now strong support for the rewarding properties of aggressive or assertive behaviors to be critical for the expression and development of adaptive...

Webb, S. J. N., Hau, J., Schapiro, S. J. 2019. Does group size matter? Captive chimpanzee (Pan troglodytes) behavior as a function of group size and composition. American Journal of Primatology 81(1), e22947.

The National Institutes of Health and the Association of Zoos and Aquariums recommend that captive chimpanzees be housed in multi‐male, multi‐female, age‐diverse groups of no less than seven individuals. These recommendations are rooted in the...

Williams, E., Carter, A., Hall, C. et al. 2019. Social interactions in zoo-housed elephants: Factors affecting social relationships. Animals 9(10), 747.

Elephants have complex social systems that are predominantly driven by ecological factors in situ. Within zoos, elephants are held in relatively static social groups and the factors observed driving social relationships in the wild are...

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...

Kutsukake, N., Teramoto, M., Honma, S. et al. 2019. Behavioural and hormonal changes during group formation by male chimpanzees. Behaviour 156(2), 109-129.

Group housing of socially-deprived individuals facilitates welfare and socialisation of primates. Here, we studied behavioural and hormonal changes in the course of group formation among nine male chimpanzees, Pan troglodytes. Aggression, reassurance, and grooming were...