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...

Fink, L. B., Mukobi, A., Gruber, L. et al. 2022. Longitudinal analysis of variability in fecal glucocorticoid metabolite concentrations in three orangutans (Pongo pygmaeus pygmaeus and Pongo pygmaeus abelii) before, during, and after transition from a regular habitat environment to temporary housing in indoor holding facilities. Animals 12(23), 3303.

Considerable research has been conducted on the effects of inter-institutional transfers, but far less consideration has been given to intra-institutional transfers and extended housing in off-habitat holding. On 15 May 2018, The Oregon Zoo’s orangutans...

Brando, S., Coe, J. 2022. Confronting back-of-house traditions: Primates as a case study. Journal of Zoological and Botanical Gardens 3(3), 366–397.

This review commentary focuses on traditional management practices and facility design with suggested improvements in non-public primate management areas, often called “back-of-house”, (henceforth BOH) in zoos, sanctuaries, and research facilities. Progress has been made toward...

Leeds, A., Boyer, D., Ross, S. R. et al. 2021. Patterns of wounding in mixed-sex social groups of western lowland gorillas (Gorilla gorilla gorilla). Applied Animal Behaviour Science 236, 105226.

Long-term, multi-institutional assessments have become a reliable tool for evaluating patterns of wounding in zoo-living primates, with results informing on best practices for species-specific care protocols and population management strategies. For western lowland gorillas (Gorilla...

O’Malley, M., Woods, J. M., Byrant, J. et al. 2021. How is Western lowland gorilla (Gorilla gorilla gorilla) behavior and physiology impacted by 360 degree visitor viewing access? Animal Behavior and Cognition 8(4), 468–480.

The effect visitors may have on the welfare of professionally managed animals is vital to consider. The present study utilized an experimental approach to examine how 360° visitor viewing access (i.e., viewing from all sides...

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...

Leeds, A., Good, J., Schook, M. W. et al. 2020. Evaluating changes in salivary oxytocin and cortisol following positive reinforcement training in two adult male western lowland gorillas (Gorilla gorilla gorilla). Zoo Biology 39(1), 51-55.

Positive reinforcement training (PRT) is associated with increases in species-typical behavior and decreases in stereotypic and abnormal behavior in participating animals. Physiological changes following PRT, for example, increases in oxytocin (OXT) and/or decreases in cortisol...

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...

Dezecache, G., Bourgeois, A., Bazin, C. et al. 2019. Orangutans' comprehension of zoo keepers' communicative signals. Animals 9(6), 300.

Zoological institutions often encourage cooperative interactions between keepers and animals so as to promote animals' welfare. One useful technique has been conditioning training, whereby animals learn to respond to keepers' requests, which facilitates a number...

Heintz, M. R.; Fuller, G., Allard, S. 2019. Exploratory investigation of infrared thermography for measuring gorilla emotional responses to interactions with familiar humans. Animals 9(9), 604.

Interactions between zoo professionals and animals occur regularly and are believed to be enriching for animals. Little empirical information exists on how animals perceive these interactions, and particularly how the interactions affect the emotional states...

Anderson, J. R., Ang, M. Y. L., Lock, L. C. et al. 2019. Nesting, sleeping, and nighttime behaviors in wild and captive great apes. Primates 60(4), 321–332.

The past few decades have seen a burgeoning of scientific studies on great apes’ use of nests for sleeping in the wild, as well as their nesting behavior and sleep in captivity. We review recent...

Cronin, K. A., Bethell, E. J., Jacobson, S. L. et al. 2018. Evaluating mood changes in response to anthropogenic noise with a response-slowing task in three species of zoo-housed primates. Animal Behavior and Cognition 5(2), 209–221.

In the zoo environment, anthropogenic noise is common as sound levels fluctuate due to visitors, construction, habitat design, and special events. In this study, changes in the mood of three species of zoo-housed primates in...

Roth, T. S., Bionda, T. R., Sterck, E. H. M. 2017. Recapturing the canopy: Stimulating Bornean orang-utan (Pongo pygmaeus) natural locomotion behaviour in a zoo environment. Journal of Zoo and Aquarium Research 5(1), 16-24.

Orang-utans are the largest mainly arboreal animal: wild orang-utans rarely come to the forest floor. In contrast, the locomotion behaviour of captive orang-utans encompasses more time on the ground and they spend less time on...

Ross, S. R., Shender, M. A. 2016. Daily travel distances of zoo-housed chimpanzees and gorillas: Implications for welfare assessments and space requirements. Primates 57(3), 395-401.

The degree to which the relatively smaller area of artificial environments (compared with natural habitats) has measureable effects on the behavior and welfare of captive animals has been debated for many years. While there is...

O'Keefe, S. 2016. Non-human primate housing facility at Newcastle University. Animal Technology and Welfare 15(2), 131-132.

Monkeys first arrived in the Comparative Biology Centre (CBC) at Newcastle University in 2000. They were housed in three small separate units consisting of steel and wooden cages. In 2011 a decision was made to...

Bayne, K. A., Beaver, B. V., Mench, J. A. et al. 2015. Laboratory animal behavior. In: Laboratory Animal Medicine, 3rd edition. Fox, J. G., Anderson, L., Otto, G., et al. (eds). Elsevier, Inc., Amsterdam, NL. pp. 1617-1651.

The study of laboratory animal behavior has increased steadily over the last decade, with expanding emphasis on a variety of commonly used species. In the United States, this trend was initially focused on species for...

Smith, J. J. 2014. Human-animal relationships in zoo-housed orangutans (P. abelii) and gorillas (G. g. gorilla): The effects of familiarity. American Journal of Primatology 76(10), 942-955.

I examined human-animal relationships (HARs) in zoo-housed orangutans (Pongo abelii) and gorillas (Gorilla gorilla gorilla) to see if they followed patterns similar to conspecific relationships in great apes and humans. Familiarity and social relationships guide...

Kurtycz, L. M., Wagner, K. E., Ross, S. R. 2014. The choice to access outdoor areas affects the behavior of great apes. Journal of Applied Animal Welfare Science 17(3), 185–197.

Outdoor access is often cited as a critical component of appropriate housing for great apes in captivity, and although studies have shown that offering primates choices can improve welfare, choice to access specific areas has...

Chelluri, G. I., Ross, S. R., Wagner, K. E. 2013. Behavioral correlates and welfare implications of informal interactions between caretakers and zoo-housed chimpanzees and gorillas. Applied Animal Behaviour Science 147, 306-315.

In captive animal facilities, human staff members are a relevant part of the animals’ social environment in addition to providing care and managing the social group. Structured, predictable interactions and relaxed, spontaneous contacts may all...

Hrapkiewicz, K., Colby, L. A., Denison, P. 2013. Clinical Laboratory Animal Medicine: An Introduction (4th Ed). Wiley-Blackwell, Ames, IA.

Clinical Laboratory Animal Medicine: An Introduction, Fourth Edition offers a user-friendly guide to the unique anatomy and physiology, care, common diseases, and treatment of small mammals and nonhuman primates. Carefully designed for ease of use...

Baumans, V., Bennett, K., Donnelly, M. et al. 2013. The problem with the dark bottom-row cage for non-human primates: A discussion by the Laboratory Animal Refinement & Enrichment Forum. Animal Technology and Welfare 12, 111-114.

Since there is evidence that the bottom cages can impact research, this should be a good reason to eliminate the two-tier system with its species-inappropriate bottom-tier cages.

Ross, S. R., Calcutt, S., Schapiro, S. J. et al. 2011. Space use selectivity by chimpanzees and gorillas in an indoor/outdoor enclosure. American Journal of Primatology 73(2), 197-208.

We used four years of detailed data on where 23 great apes (chimpanzees and gorillas) positioned themselves within a modern, indoor/outdoor zoo enclosure to determine not only how the apes utilized their space but also...

Coleman, K. 2011. Caring for nonhuman primates in biomedical research facilities: Scientific, moral and emotional considerations. American Journal of Primatology 73(3), 220-225.

Animal care for nonhuman primates (NHPs) in biomedical facilities has undergone major changes in the past few decades. Today, most primate facilities have dedicated and highly trained animal care technicians who go to great efforts...

Bortolini, T. S., Bicca-Marques, J. C. 2011. The effect of environmental enrichment and visitors on the behaviour and welfare of two captive hamadryas baboons (Papio hamadryas). Animal Welfare 20(4), 573-579.

The welfare of zoo animals depends on a combination of physical, social, dietary and other ecological characteristics of the captive setting. We analysed the influence of the transfer of an adult couple of hamadryas baboons...

Waitt, C. D., Bushmitz, M., Honess, P. E. 2010. Designing environments for aged primates. Laboratory Primate Newsletter, 49(3), 5-9.

In order to prevent physical and psychological deterioration in older animals, it is important to apply the same principles of environmental enrichment and housing as are applied to younger animals. As we have discussed above...