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. 
Eagan, T. 2019. Evaluation of enrichment for reptiles in zoos. Journal of Applied Animal Welfare Science 22(1), 69-77.

Studies on environmental enrichment for reptiles are lacking in the scientific literature. Although the literature reflects a limited take on reptile enrichment in the zoological community, it may not be the case in reality as...

Sherwen, S. L., Hemsworth, P. H. The visitor effect on zoo animals: Implications and opportunities for zoo animal welfare. Animals 9(6), 366.

Achieving and maintaining high standards of animal welfare is critical to the success of a modern zoo. Research has shown that an animal's welfare is highly dependent on how various individual animal factors (e.g., species...

Mastellone, V., Bovera, F., Musco, N. et al. 2019. Mirrors improve rabbit natural behavior in a free-range breeding system. Animals 9(8), 533.

The aim of this research was to evaluate the possible usefulness of mirrors in improving rabbit behavior in a free-range breeding system. Three groups (each consisting of nine replicates of three animals) were compared: isolated...

Trocino, A., Zomeño, C., Filiou, E. et al. 2019. The use of environmental enrichments affects performance and behavior of growing rabbits housed in collective pens. Animals 9(8), 537.

This study assessed the effects of an elevated plastic-slatted platform and/or a plastic hiding tube in collective pens with large group sizes (27 or 36 rabbits/pen; 16 rabbits/m2) on the performance and welfare of rabbits...

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...

Bliss-Moreau, E., Baxter, M. G. 2019. Interest in non-social novel stimuli as a function of age in rhesus monkeys. Royal Society Open Science 6(9), 182237.

Human cognitive and affective life changes with healthy ageing; cognitive capacity declines while emotional life becomes more positive and social relationships are prioritized. This may reflect an awareness of limited lifetime unique to humans, leading...

Animal Welfare Institute. 2019. Let’s get serious about animal play. AWI Quarterly 68(3) Fall, 19.

This article describes the importance of providing laboratory animals with opportunities to engage in play, and provides a few practical ideas for how to do this.

Animal Welfare Institute. 2019. Rabbit enrichment items: Getting bang for the buck (and doe). AWI Quarterly 68(1) Spring, 24-25.

A recent discussion on the Laboratory Animal Refinement and Enrichment Forum (LAREF) focused on new enrichment ideas for rabbits. Contributors shared their experiences about which toys and treats get rave reviews from rabbits.

Heyworth, C. 2019. Inventive enrichment to facilitate weight gain in the common marmoset (Callithrix jacchus) during invasive studies. Laboratory Animal Science Professional 7(4) (December), 38-41.

To provide the highest standard of care to marmosets during invasive surgical studies, studies that often lead to weight loss, it is paramount to call upon inherent species-specific enrichment tactics to mitigate weight loss. Weight...

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...

Egelkamp, C. L., Ross, S. R. 2019. A review of zoo-based cognitive research using touchscreen interfaces. Zoo Biology 38(2), 220-235.

In the past few decades, there has been an increase in the number of zoo-based touchscreen studies of animal cognition around the world. Such studies have contributed to the field of comparative cognition despite the...

Cox, R. J., Nol, P., Ellis, C. K. et al. 2019. Research with agricultural animals and wildlife. ILAR Journal 60(1), 66-73.

In fiscal year 2016, agricultural animals such as swine, sheep, goats, and cattle represented 10% of the 820 812 animals used in USDA-regulated research. In addition to traditional agricultural animals, research studies using captive wildlife...

Wooddell, L. J., Beisner, B., Hannibal, Darcy L. et al. 2019. Increased produce enrichment reduces trauma in socially-housed captive rhesus macaques (Macaca mulatta). American Journal of Primatology 81(12), e23073.

Due to primate adaptations for sociality, captive rhesus macaques have optimal welfare and utility as a biomedical model when they can be maintained in outdoor social groups. As a despotic species; however, aggression can result...

Schmitt, V. 2019. Implementing portable touchscreen-setups to enhance cognitive research and enrich zoo-housed animals. Journal of Zoo and Aquarium Research 7(2), 50-58.

To understand the evolutionary development of cognition, comparing the cognitive capacities of different animal species is essential. However, getting access to various species with sufficient sample sizes can be very challenging. Zoos, housing large ranges...

Borgmans, G., Palme, R., Sannen, A., et al. 2018. The effect of environmental provisioning on stress levels in captive green anole (Anolis carolinensis). Animal Welfare 27(1), 35-46.

In response to an increased awareness concerning the welfare of captive animals, several studies have investigated the effect of provisions on stress levels in model species, such as small mammals, birds and fish. In contrast...

Lutz, C. K., Brown, T. A. 2018. Porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). JAALAS 57(2), 138-142.

Effective environmental enrichment is used by animals, promotes species-typical behavior, and decreases abnormal behavior. Porches attached to the front of an animal's cage provide additional space, perching opportunities, and a better view of the surroundings...

Cabana, F., Maguire, R., Hsu, C-D. et al. 2018. Identification of possible nutritional and stress risk factors in the development of marmoset wasting syndrome. Zoo Biology 37(2), 98–106.

Marmoset wasting syndrome (MWS) describes a series of symptoms in callitrichids that lead to general weakness and a failure to thrive in captive conditions such as zoological institutions. Though the cause of MWS has not...

Fuller, G., Murray, A., Thueme, M. et al. 2018. Behavioral and hormonal responses to the availability of forage material in Western lowland gorillas (Gorilla gorilla gorilla). Zoo Biology 37(1), 23–34.

We investigated how forage material affects indicators of welfare in three male Western lowland gorillas (Gorilla gorilla gorilla) at the Detroit Zoo. In addition to their maintenance diet and enrichment foods, the gorillas generally received...

Hawkins, P., McBride, A., Paiba, G. et al. 2018. Report of the 2017 RSPCA/UFAW Rodent and Rabbit Welfare Group meeting. Animal Technology and Welfare 17(2), 75-83. [Meeting Report]

The RSPCA/UFAW Rodent (and now Rabbit) Welfare Group held a one-day meeting on 14 November 2017 in Weybridge, UK. The first session addressed meeting animals' needs and aiming for a 'good life', with the needs...

Pearson, K., Gant, J. 2018. Improving rabbit enrichment: Developing a rolling enrichment plan. Animal Technology and Welfare 17(2), 121-123.

A three-week enrichment preference study trialling different substrates, food and pen structures was carried out in three, group-housed female New Zealand White Rabbits (NZW). Preference results: structural - rabbits spent the most time with a...

Brown, T. A., Lutz, C. K., 2018. An assessment of porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). American Journal of Primatology 80(S1), 18 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #21).

Effective environmental enrichment encourages usage, promotes species‐typical behaviors, and/or decreases abnormal behaviors. Porches are small cages that attach to the primary cage of an animal to provide additional space and a better view of the...

Perlman, J. E., Martin, A. L., Bloomsmith, M. A., 2018. Increases in feeding and destructible enrichment distribution in caged rhesus macaques (Macaques mulatta) provide some behavioral benefits. American Journal of Primatology 80(S1), 19 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #24).

It is important to evaluate the effectiveness of environmental enrichment in meeting behavioral goals (e.g., decreasing abnormal behavior) and in making the best use of limited facility resources (e.g., money, personnel time). One/zero behavioral data...

Woelffer, S., Ace, L., Sullivan, J. et al., 2018. Enhanced physical environment in single-housed macaques: A long-term usage profile of cage extensions. American Journal of Primatology 80(S1), 19-20 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #25).

Social housing is always preferred in the research environment; however, single housing is sometimes necessitated by scientific objectives or social incompatibility. In these cases, other environmental enhancements are developed to provide indirect social interactions. We...

Pomerantz, O., Nyandwi, S., Baker, K., 2018. Providing feeding enrichment by hand mitigates anxiety among laboratory-housed rhesus macaques (Macaca mulatta). American Journal of Primatology 80(S1), 20 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #26).

Some husbandry procedures may be perceived as aversive by cage‐housed rhesus macaques. We assessed whether providing feeding enrichment by hand as opposed to placing it on a caging surface decreases anxiety responses to daily husbandry...

Yoshimoto, T., Takahashi, E., Yamashita, S. et al. 2018. Larger cages with housing unit environment enrichment improve the welfare of marmosets. Experimental Animals 67(1), 31-39.

The provision of adequate space for laboratory animals is essential not only for good welfare but accurate studies. For example, housing conditions for primates used in biomedical research may negatively affect welfare and thus the...