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. 
Ross, M., Garland, A., Harlander-Matauschek, A. et al. 2019. Welfare-improving enrichments greatly reduce hens' startle responses, despite little change in judgment bias. Scientific Reports 9, 11881.

Responses to ambiguous and aversive stimuli (e.g. via tests of judgment bias and measures of startle amplitude) can indicate mammals’ affective states. We hypothesised that such findings generalize to birds, and that these two responses...

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...

Fernandez, E. J., Kinley, R. C., Timberlake, W. 2019. Training penguins to interact with enrichment devices for lasting effects. Zoo Biology 38(6), 481-489.

The modern zoo has brought about two major advances in the behavioral welfare of their exhibited animals: (a) The use of environmental enrichment to promote naturalistic behaviors and (b) the use of training to improve...

Jung, L., Knierim, U. 2019. Differences between feather pecking and non-feather pecking laying hen flocks regarding their compliance with recommendations for the prevention of feather pecking – A matched concurrent case-control design. Applied Animal Behaviour Science 219, 104839.

Feather pecking (FP) is a multifactorial problem in all housing systems. Using a case-control design we wanted to determine a set of variables which may be decisive for a flock to become case or control...

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...

Špinka, M. 2019. Animal agency, animal awareness and animal welfare. Animal Welfare 28(1), 11–20.

In nature, animals need to actively engage with the environment in order to prosper in survival and reproduction. Hence, agency is a central adaptive characteristic of animal life. In this paper, I propose that from...

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...

de Almeida A. C., Palme, R., Moreira, N. 2018. How environmental enrichment affects behavioral and glucocorticoid responses in captive blue-and-yellow macaws (Ara ararauna). Applied Animal Behaviour Science 201, 125-135.

Captive animals are susceptible to chronic stress due to restricted space, lack of hiding places, presence of visitors, or the lack of resources that promote physical and mental stimuli. In birds, chronic stress can promote...

Hunniford, M. E., Widowski, T. M. 2018. Curtained nests facilitate settled nesting behaviour of laying hens in furnished cages. Applied Animal Behaviour Science 202, 39-45.

Egg location can be used to determine the nests that hens prefer, but it does not indicate whether the design of that nest satisfies a hen’s nesting motivation. Hens that are satisfied with the nest...

Hunniford, M. E., Mason, G. J., Widowski, T. M. 2018. Laying hens’ preferences for nest surface type are affected by enclosure. Applied Animal Behaviour Science 201, 7-14.

The nest surfaces preferred by hens are inconsistent with those typically provided in commercial settings. However, little research has explored hens’ preferences for commercially available nest surfaces. Our objective was to compare hens’ preferences for...

Liu, K., Xin, H., Shepherd, T. et al. 2018. Perch-shape preference and perching behaviors of young laying hens. Applied Animal Behaviour Science 203, 34-41.

Provision of perches in enriched colony or cage-free hen housing facilitates birds’ ability to express natural behaviors, thus enhancing animal welfare. Although considerable research has been conducted on poultry perches, further investigation is needed of...

Jung, L., Knierim, U. 2018. Are practice recommendations for the prevention of feather pecking in laying hens in non-cage systems in line with the results of experimental and epidemiological studies? Applied Animal Behaviour Science 200, 1-12.

Feather pecking (FP) in laying hens is an important animal welfare problem in practice, despite extensive research and increasing sources of advice for farmers. We aimed to give an overview over results from experimental and...

Gebhardt-Henrich, S. G., Toscano, M. J., Würbel, H. 2018. Use of aerial perches and perches on aviary tiers by broiler breeders. Applied Animal Behaviour Science 203, 24-33.

Perching, especially during the night, is an innate behaviour of chickens and the provision of perches is mandatory for laying hens in multiple countries. We examined whether broiler breeders of the fast (Ross 308) and...

Baxter, M., Bailie, C. L., O’Connell, N. E. 2018. Evaluation of a dustbathing substrate and straw bales as environmental enrichments in commercial broiler housing. Applied Animal Behaviour Science 200, 78-85.

The use of straw bales as an environmental enrichment is common for broiler chickens in enriched housing systems, however relatively little information exists about their effectiveness in improving welfare. There has also been no widespread...

Bailie, C. L., Baxter, M., O’Connell, N. E. 2018. Exploring perch provision options for commercial broiler chickens. Applied Animal Behaviour Science 200, 114-122.

Two related experiments involving broiler chickens are presented. Experiment 1 evaluated the use of six perch types: (1) an A-frame design (incorporating a platform and ramps), (2) a ‘flat top’ ramp, (3) a curved ramp...

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...

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...

Campbell, D. L. M., Horton, B. J., Hinch, G. N. 2018. Using radio-frequency identification technology to measure synchronised ranging of free-range laying hens. Animals 8(11), 210.

Free-range laying hen systems provide individuals a choice between indoor and outdoor areas where range use may be socially influenced. This study used radio-frequency identification technology to track the ranging of individually-tagged hens housed in...

Perkovic, K., Mettke-Hofmann, C. 2018. Colour polymorphic Gouldian finches avoid complex backgrounds but prefer simple camouflage colours over white backgrounds. Applied Animal Behaviour Science, 206, 102-108.

Many animals blend in well with their environment known as camouflage which is a successful predator avoidance strategy. However, captive environments often do not allow for camouflage and may result in stress and reduced welfare...

Tahamtani, F. M., Pedersen, I. J., Toinon, C. et al. 2018. Effects of environmental complexity on fearfulness and learning ability in fast growing broiler chickens. Applied Animal Behaviour Science 207, 49-56.

Increasing environmental complexity, i.e. by providing environmental enrichment, has been suggested as a way to improve broiler chicken welfare. One issue affecting broiler welfare is the level of fearfulness of the flock. Exaggerated fear responses...