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. 
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...

Kanghae, H., Thongprajukaew, K., Inphrom, S. et al. 2021. Enrichment devices for green turtles (Chelonia mydas) reared in captivity programs. Zoo Biology 40(5), 407-416.

Environmental enrichment supports the well-being and welfare of captive animals. In the current study, the most suitable form of enrichment device for captive green turtles (Chelonia mydas) was investigated, to support head-start programs rearing turtles...

Laméris, D. W., Verspeek, J., Depoortere, A. et al. 2021. Effects of enclosure and environmental enrichment on the behaviour of ring-tailed lemurs (Lemur catta). Journal of Zoological and Botanical Gardens 2(2), 164–173.

Environmental enrichment is widely used to improve the quality of life of animals under human care. To successfully implement enrichment programs, it is important to evaluate their effect in different enclosure types since housing conditions...

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...

Waterman, J. O., McNally, R., Harrold, D. et al. 2021. Evaluating environmental enrichment methods in three zoo-housed varanidae lizard species. Journal of Zoological and Botanical Gardens 2(4), 716–727.

Environmental enrichment has been shown to enhance the behavioural repertoire and reduce the occurrence of abnormal behaviours, particularly in zoo-housed mammals. However, evidence of its effectiveness in reptiles is lacking. Previously, it was believed that...

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...

Skalníková, P., Frynta, D., Abramjan, A. et al. 2020. Spontaneous color preferences in rhesus monkeys: What is the advantage of primate trichromacy? Behavioural Processes 174, 104084.

Color perception and color signaling play an important role in various aspects of animal behavior. However, in mammals, trichromatic vision characterized by three retinal photopigments tuned to peak short, middle and long wavelengths is limited...

Regaiolli, B., Angelosante, C., Marliani, G. et al. 2020. Gum feeder as environmental enrichment for zoo marmosets and tamarins. Zoo Biology 39(2), 73-82.

Tamarins and marmosets are small-bodied social callitrichines. Wild callitrichines feed on exudates, such as sap and gum; particularly, marmosets are mainly gummivores, while tamarins consume gums only occasionally and opportunistically. Zoo marmosets and tamarins are...

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...

Zemanova, M. A. 2020. Towards more compassionate wildlife research through the 3Rs principles: Moving from invasive to noninvasive methods. Wildlife Biology 2020(1), no page numbers.

Research in ecology and wildlife biology remains crucial for increasing our knowledge and improving species management and conservation in the midst of the current biodiversity crisis. However, obtaining information on population status often involves invasive...

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...

Buchanan, K. 2020. DIY: Foraging balls. Laboratory Animal Science Professional 8(3) (May/June), 51.

This article describes the steps for making a DIY guinea pig or rabbit cardboard foraging ball. Pictures are provided for each step as well as the completed ball. These cardboard foraging balls can be made...

Hedenqvist, P., Trbakovic, A., Mellgren, T. et al. 2020. The effect of housing environment on bone healing in a critical radius defect in New Zealand white rabbits. PLOS ONE 15(5), e0233530.

In animal studies on bone healing, the effect of housing space and physical activity are seldom taken into account. Bone formation was evaluated in New Zealand White rabbits (mean ± SEM BW: 3.9 ± 0.11...

Kneeland, M. R., Spagnuolo, V. A., Evers, D. C. et al. 2020. A novel method for captive rearing and translocation of juvenile common loons. Zoo Biology 39(4), 263–270.

Common loons (Gavia immer) are diving waterbirds that are particularly challenging to keep in captivity due to their specific behavioral and physiologic needs, special housing requirements, and susceptibility to stress‐related disease. We report a novel...

Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...

Hosking, A., Martinic, G. 2020. The care of the Children’s Python (Antaresia childreni). Animal Technology and Welfare 19(2), 118-122.

This article describes the care of the Children’s python (Antaresia childreni). It includes information on housing, feeding, handling, as well as the general health care of these animals. The information presented is derived from Standard...

Hosking, A., Martinic, G. 2020. The care of Central and Pygmy bearded dragons. Animal Technology and Welfare 19(2), 125-130.

This article describes the care of central bearded dragons (Pogona vitticeps) as well as Pygmy bearded dragons (Pogona henrylawsoni). It includes information on housing, feeding, handling and sexing technique, as well as the general health...

Worlds, T., Kearney, M., De La Garza, F. et al. 2020. Development of a rabbit enrichment program and contribution to a culture of transparency and care. Laboratory Animal Science Professional 8(6) (November/December), 38-40.

The Becton Dickinson (BD) Research Animal Care Program has developed an acclimation and enrichment program that has enhanced animal welfare for studies requiring single housing, contributed to a culture of care, increased transparency, and improved...

Greene, L. K., Clarke, T. A., Southworth, C. A. et al. 2020. Daily lettuce supplements promote foraging behavior and modify the gut microbiota in captive frugivores. Zoo Biology 39(5), 334-344.

For captive primates, greater provisioning of leafy greens or foliage can promote natural foraging behavior while boosting fiber intake. Recalcitrant fiber, although minimally available to endogenous metabolism, is readily fermented into nutrients by gut microbes...

Munari, C., Ponzio, P., Macchi, E. et al. 2020. A multifactorial evaluation of different reproductive rhythms and housing systems for improving welfare in rabbit does. Applied Animal Behaviour Science 230, 105047.

The most widespread reproductive rhythm practiced in rabbit farming is based on artificial insemination (AI) performed at around 11 days pospartum. This approach results in high production rates, but requires high yearly replacement of animals...

Verspeek, J., Stevens, J. M. G. 2020. Food preference and nutrient composition in captive bonobos (Pan paniscus). Primates 61(5), 661-671.

Food preference has been studied in a range of Hominoidea in the wild and in captivity, allowing for interspecific comparisons. Chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla gorilla) prefer low-fibre, high-sugar foods, suggesting that frugivory...

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...

McMahon, S. A., Wigham, E. 2020. ‘All Ears’: A questionnaire of 1516 owner perceptions of the mental abilities of pet rabbits, subsequent resource provision, and the effect on welfare. Animals 10(10), 1730.

Pet rabbit welfare is a hidden crisis: Inappropriately housed, fed, and not routinely provided healthcare—rabbits can often suffer painful conditions and shortened lifespans. This study provides novel understanding of owners’ perceptions of rabbits’ mental capabilities...