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...

Hammer, R., Stribos, M. S., Boehm, P. M. et al. 2023. A novel methodological approach for group classification during fission of a semi-free-ranging group of Japanese macaques (Macaca fuscata). American Journal of Primatology 85(2), e23463.

The self-initiated split of a social group, known as fission, is a challenge faced by many group-living animals. The study of group fission and the social restructuring process in real time provides insights into the...

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...

Tomeczko, S. 2022. Interpreting macaque facial expressions and body behavior in preparation for social housing. Laboratory Animal Science Professional 10(1) (January/February), 62-63.

This article will help those who are new to working with non-human primates. Interpreting macaque facial expressions and body behavior is important for beginning the process of pair housing two animals.

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...

Yamanashi, Y., Nemoto, K., Alejandro, J. 2021. Social relationships among captive male pygmy slow lorises (Nycticebus pygmaeus): Is forming male same-sex pairs a feasible management strategy? American Journal of Primatology 83, e23233.

Little is known about the social behavior of pygmy slow lorises, in particular, the social relationships of same‐sex individuals have rarely been investigated. The Slow Loris Conservation Center was built at the Japan Monkey Center...

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...

Cowl, V. B., Walker, S. L., Shultz, S. 2021. Reproductive males are effective at managing conflict in captive Sulawesi crested macaques (Macaca nigra). American Journal of Primatology 83(7), e23266.

Group size, density, and composition significantly influence the expression of agonism and, as demography is frequently manipulated in captivity, natural mechanisms of conflict management may be disrupted. Here, we examine how changes to the social...

Bailey, K. L., Bloomsmith, M. A., Michopoulos, V. et al. 2021. Influence of female coalitionary aggressive behavior on the success of male introductions to female groups of rhesus macaques (Macaca Mulatta). Applied Animal Behaviour Science 237, 105293.

Migration patterns of wild rhesus macaque males are often mimicked in captivity by introducing unfamiliar males to female groups every few years. This strategy prevents inbreeding and has been shown to encourage group stability once...

Pomerantz, O., Capitanio, J. P. 2021. Temperament predicts the quality of social interactions in captive female rhesus macaques (Macaca mulatta). Animals 11(8), 2452.

Previous reports suggest that female macaques with greater similarity in emotionality and nervous temperament, as evaluated in a well-established BioBehavioral Assessment (BBA) at the California National Primate Research Center, were more likely to form successful...

Alejandro, J., Yamanashi, Y., Nemoto, K. et al. 2021. Behavioral changes of solitary housed female pygmy slow lorises (Nycticebus pygmeaus) after introduction into group enclosures. Animals 11(9), 2751.

Pygmy slow lorises (Nycticebus pygmaeus) are threatened with extinction in the wild. Their nocturnal lifestyle and small size make them difficult to study in their natural habitat, but increasing evidence suggests that they are more...

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)...

Balasubramaniam, K. N., Beisner, B. A., McCowan, B. et al. 2021. Female social structure influences, and is influenced by, male introduction and integration success among captive rhesus macaques (Macaca mulatta). Behaviour 158(11), 1007–1042.

Animal social structure is influenced by multiple socioecological factors. Of these, the links between changes to group demography through the arrival of new individuals and residents' social structure remain unclear. Across seven groups of captive...

Bwye, P. 2021. Social distancing is over: A pygmy slow loris trio housed together at Bristol Zoo Gardens. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 48(3), 15-17.

After the loss of one of our breeding males and the export of loris offspring, in 2021 our off-show female loris was solitary. During this time, we noticed a number of changes in this female...

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...

Wendler, P., Ertl, N., Flügger, M. et al. 2020. Influencing factors on the foot health of captive Asian elephants (Elephas maximus) in European zoos. Zoo Biology 39(2), 109-120.

Pathological lesions of feet occur frequently in captive elephant populations. To improve foot health, it is important to identify risk factors associated with such pathologies. Several previous studies have analyzed potentially influencing factors but were...

Mishra, P. S., Pal, A., Velankar, A. D. et al. 2020. Does rank rule? Rank-related grooming patterns in Nicobar long-tailed macaques Macaca fascicularis umbrosus. Primates 61(3), 443–453.

Primates maintain social bonds with specific individuals in the group by directing grooming toward them. Social grooming is often targeted toward individuals with whom the most benefits can be exchanged, which are usually the high-ranking...

Stocker, M. Loretto, M.-C., Sterck, E. H. M. et al. 2020. Cooperation with closely bonded individuals reduces cortisol levels in long-tailed macaques. Royal Society Open Science 7(5), 7191056.

Many animal species cooperate with conspecifics in various social contexts. While ultimate causes of cooperation are being studied extensively, its proximate causes, particularly endocrine mechanisms, have received comparatively little attention. Here, we present a study...

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...

Rothwell, E. S., Carp, S. B., Savidge, L. E. et al. 2020. Relationship tenure differentially influences pair-bond behavior in male and female socially monogamous titi monkeys (Callicebus cupreus). American Journal of Primatology 82(10), e23181.

Pair-bonded primates have uniquely enduring relationships and partners engage in a suite of behaviors to maintain these close bonds. In titi monkeys, pair bond formation has been extensively studied, but changes across relationship tenure remain...

Newman, R., McKeown, S., Power, T. et al. 2020. Introducing three new males into a captive lion-tailed macaque (Macaca silenus) group. Journal of Zoo and Aquarium Research 8(3), 212-217.

The introduction of an unfamiliar animal to a new individual or group can be highly stressful for any animal. Various studies have tried to determine the best method for introducing unfamiliar animals to each other...

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...