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...

Scott, N. L., LaDue, C. A. 2019. The behavioral effects of exhibit size versus complexity in African elephants: A potential solution for smaller spaces. Zoo Biology 38(5), 448-457.

Population-level analyses suggest that habitat complexity, but not necessarily space availability, has important welfare outcomes for elephants in human care. At the Dallas Zoo, the opening of a new exhibit complex allowed us to measure...

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...

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...

Gomes, D., McSweeney, L., Santos, M. 2019. Effects of environmental enrichment techniques on stereotypical behaviours of captive Sumatran tigers: A preliminary case study. Journal of Animal Behaviour and Biometeorology 7(4), 144-148.

Wild animals are maintained in Zoological facilities for purposes of education, conservation, research, and recreation. Several studies have proven that the surroundings of an animal's artificial habitat, as well as environmental enrichment techniques, are factors...

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...

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...

Hacker, C. E., Miller, L. J., Schulte, B. A. 2018. Examination of enrichment using space and food for African elephants (Loxodonta africana) at the San Diego Zoo Safari Park. Animal Welfare 27(1), 55-65.

Concern for elephant welfare in zoological facilities has prompted a number of exhibit and management modifications, including those involving enrichment. Knowledge of how these changes impact indicators of welfare, such as elephant movement and behaviour...

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...

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...

Hempstead, M. N., Waas, J. R., Stewart, M. et al. 2018. Evaluation of alternatives to cautery disbudding of dairy goat kids using behavioural measures of post-treatment pain. Applied Animal Behaviour Science 206, 32-38.

Alternatives to cautery disbudding (caustic paste and cryosurgical disbudding, and clove oil injection) were evaluated using behavioural measures of post-treatment pain in dairy goat kids. Fifty Saanen doe kids were randomly assigned to one of...

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...

Norman, K. I., Weeks, C. A., Pettersson, I. C. et al. 2018. The effect of experience of ramps at rear on the subsequent ability of layer pullets to negotiate a ramp transition. Applied Animal Behaviour Science 208, 92-99.

In commercial situations, laying hens must negotiate levels to reach resources such as food, water and litter. Providing ramps in aviary systems reduces collisions and resultant keel bone fractures in adults. We investigated whether providing...

Stachowicz, J., Gygax, L., Hillmann, E. et al. 2018. Dairy goats use outdoor runs of high quality more regardless of the quality of indoor housing. Applied Animal Behaviour Science 208, 22-30.

For dairy goats in loose housing, access to an outdoor run has potential welfare benefits as it provides additional space, enables spatial separation and may offer items representing behavioural enrichment for the goats (e.g. brush...

Zepp, M., Louton, H., Erhard, M. et al. 2018. The influence of stocking density and enrichment on the occurrence of feather pecking and aggressive pecking behavior in laying hen chicks. Journal of Veterinary Behavior 24, 9-18.

The housing conditions and environments experienced during the rearing period can influence the development of feather pecking in chickens during this time and in the subsequent laying period. The aim of this study was to...