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. 
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...

Wong, C.-H., Tsai, M.-A., Ko, F.-C. et al. 2023. Skin cortisol and acoustic activity: Potential tools to evaluate stress and welfare in captive cetaceans. Animals 13(9), 1521.

As people’s focus broadens from animals on farms to zoos and aquaria, the field of welfare science and the public’s concern for animal welfare continue to grow. In captive animals, stress and its causes are...

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...

Lee, V. E., Arnott, G., Turner, S. P. 2022. Social behavior in farm animals: Applying fundamental theory to improve animal welfare. Frontiers in Veterinary Science 9, 932217.

A fundamental understanding of behavior is essential to improving the welfare of billions of farm animals around the world. Despite living in an environment managed by humans, farm animals are still capable of making important...

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...

Serres, A., Xu, C., Hao, Y. et al. 2021. The click production of captive Yangtze finless porpoises (Neophocaena asiaeorientalis asiaorientalis) is influenced by social and environmental factors. Animals 11(2), 511.

Yangtze finless porpoises use high-frequency clicks to navigate, forage, and communicate. The way in which click production may vary depending on social or environmental context has never been investigated. A group of five captive Yangtze...

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...

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)...

Probert, R., Bastian, A., Elwen, S. H. et al. 2021. Vocal correlates of arousal in bottlenose dolphins (Tursiops spp.) in human care. PLOS ONE 16(9), e0250913.

Human-controlled regimes can entrain behavioural responses and may impact animal welfare. Therefore, understanding the influence of schedules on animal behaviour can be a valuable tool to improve welfare, however information on behaviour overnight and in...

Jones, B. L., Oswald, M., Tufano, S. et al. 2021. A system for monitoring acoustics to supplement an animal welfare plan for bottlenose dolphins. Journal of Zoological and Botanical Gardens 2(2), 222–233.

Animal sounds are commonly used by humans to infer information about their motivations and their health, yet, acoustic data is an underutilized welfare biomarker especially for aquatic animals. Here, we describe an acoustic monitoring system...

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...

Lopez-Marulanda, J., Rödel, H. G., Colpaert, N. et al. 2020. Contexts of emission of non-signature whistles in bottlenose dolphins (Tursiops truncatus) under human care. Behavioural Processes 181, 104255.

Bottlenose dolphins are social cetaceans that strongly rely on acoustic communication and signaling. The diversity of sounds emitted by the species has been structurally classified into whistles, clicks and burst-pulsed sounds. Although click sounds and...

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...

Brown, J. L., Carlstead, K., Bray, J. D. et al. 2019. Individual and environmental risk factors associated with fecal glucocorticoid metabolite concentrations in zoo-housed Asian and African elephants. PLOS ONE 14(9), e0217326.

A recent large-scale welfare study in North America involving 106 Asian (Elephas maximus) and 131 African (Loxodonta africana) elephants at 64 accredited facilities identified links (i.e., risk factors) between zoo environmental factors and a number...

Sánchez–Hernández, P., Krasheninnikova, A., Almunia, J. et al. 2019. Social interaction analysis in captive orcas (Orcinus orca). Zoo Biology 38(4), 323-333.

The management of socially complex species in captivity is challenging. Research on their social behavior improves our understanding of interactions in captive animals and captive-group management. We conducted a detailed analysis of social relationships shown...

Schiffmann, C., Clauss, M. 2019. Impact of a new exhibit on stereotypic behavior in an elderly captive African elephant. Journal of Zoo and Aquarium Research 7(1), 37-43.

Stereotypic behavior in zoo elephants is considered an indicator of impaired welfare. The underlying causes are diverse and many aspects are still unexplored. Nevertheless, many zoological institutions take huge efforts to improve the well-being of...

Brown, J. L., Paris, S., Prado-Oviedo, N. A. 2016. Reproductive health assessment of female elephants in North American zoos and association of husbandry practices with reproductive dysfunction in African Elephants (Loxodonta africana). PLOS ONE 11(7), e0145673.

As part of a multi-institutional study of zoo elephant welfare, we evaluated female elephants managed by zoos accredited by the Association of Zoos and Aquariums and applied epidemiological methods to determine what factors in the...

Holdgate, M. R., Meehan, C. L., Hogan, J. N. et al. 2016. Walking behavior of zoo elephants: Associations between GPS-measured daily walking distances and environmental factors, social factors, and welfare indicators. PLOS ONE 11(7), e0150331.

Research with humans and other animals suggests that walking benefits physical health. Perhaps because these links have been demonstrated in other species, it has been suggested that walking is important to elephant welfare, and that...

Meehan, C. L., Hogan, J. N., Bonaparte-Saller, M. K. et al. 2016. Housing and social environments of African (Loxodonta africana) and Asian (Elephas maximus) elephants in North American zoos. PLOS ONE 11(7), e0146703.

We evaluated 255 African (Loxodonta africana) and Asian (Elephas maximus) elephants living in 68 North American zoos over one year to quantify housing and social variables. All parameters were quantified for the both the day...

Holdgate, M. R., Meehan, C. L., Hogan, J. N. et al. 2016. Recumbence behavior in zoo elephants: Determination of patterns and frequency of recumbent rest and associated environmental and social factors. PLOS ONE 11(7), e0153301.

Resting behaviors are an essential component of animal welfare but have received little attention in zoological research. African savanna elephant (Loxodonta africana) and Asian elephant (Elephas maximus) rest includes recumbent postures, but no large-scale investigation...

Hill, H., Guarino, S., Crandall, S. et al. 2015. Young belugas diversify adult beluga (Delphinapterus leucas) behavior. Animal Behavior and Cognition 2(3), 267–284.

Across the animal kingdom, immature animals are characterized by their playfulness and diversity of behavior, but are their actions enriching to adult conspecifics? The purpose of this study was to assess if beluga (Delphinapterus leucas)...