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. 
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...

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...

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...

Liu, K., Xin, H. 2017. Effects of horizontal distance between perches on perching behaviors of Lohmann Hens. Applied Animal Behaviour Science 194, 54-61.

Perching is a highly-motivated natural behavior of laying hens that has been considered as one of the essential welfare requirements. The objective of the study was to evaluate perching behaviors of laying hens as affected...

Brantsæter, M., Tahamtani, F. M., Nordgreen, J. et al. 2017. Access to litter during rearing and environmental enrichment during production reduce fearfulness in adult laying hens. Applied Animal Behaviour Science 189, 49-56.

Exaggerated fear-reactions are associated with injurious flying, smothering, feather pecking and other events that compromise animal welfare in laying hens. The aim of this study was to test the hypothesis that chicks with access to...

Hunniford, M. E., Widowski, T. M. 2017. Nest alternatives: Adding a wire partition to the scratch area affects nest use and nesting behaviour of laying hens in furnished cages. Applied Animal Behaviour Science 186, 29-34.

Furnished cages (FC) are designed to accommodate highly motivated behaviour patterns like nesting; however, how hens perceive the resources provided in FCs is not fully understood. Our previous research of hens in FCs with a...

Pettersson, I. C., Weeks, C. A., Nicol, C. J. 2017. The effect of ramp provision on the accessibility of the litter in single and multi-tier laying hen housing. Applied Animal Behaviour Science 186, 35-40.

Level changes in commercial laying hen loose-housing systems may be physically difficult for birds to negotiate, preventing or limiting access to resources such as the litter area and the outdoor range, and potentially increasing injury...

Pettersson, I. C., Weeks, C. A., Nicol, C. J. 2017. Provision of a resource package reduces feather pecking and improves ranging distribution on free-range layer farms. Applied Animal Behaviour Science 195, 60-66.

The effect of a resource package designed to reduce inter-bird pecking and increase range use was tested on fourteen free-range farms in the UK. The package comprised two types of objects intended to attract pecking...

Keeling, L. J., Newberry, R. C., Estevez, I. 2017. Flock size during rearing affects pullet behavioural synchrony and spatial clustering. Applied Animal Behaviour Science 194, 36-41.

Animals are often synchronised in their behaviour, with costs and benefits varying according to group size and the behaviour being performed. Making decisions about optimal allocation and distribution of resources to animals in our care...

Stadig, L. M., Rodenburg, T. B., Ampe, B. et al. 2017. Effect of free-range access, shelter type and weather conditions on free-range use and welfare of slow-growing broiler chickens. Applied Animal Behaviour Science 192, 15-23.

Free-range access for broiler chickens can benefit animal welfare because the birds have access to a more natural environment and more opportunities to perform natural behaviours than in indoor systems. Also, they have more space...

Rault, J.-L., Taylor, P. S. 2017. Indoor side fidelity and outdoor ranging in commercial free-range chickens in single- or double-sided sheds. Applied Animal Behaviour Science 194, 48-53.

The ranging behaviour of broiler chickens kept in free-range housing systems remains poorly understood, despite access to the outdoor range being their main feature. We investigated the impact of allowing chickens to have range access...

Meng, F., Chen, D., Li, X. et al. 2017. The effect of large or small furnished cages on behaviors and tibia bone of laying hens. Journal of Veterinary Behavior 17, 69-73.

This study aimed to investigate the effects of large furnished cages (LFCs) or small furnished cages (SFCs) on behavior and tibia bone of laying hens. Three hundred and sixty Hyline brown hens at 16 weeks...

Rayner, A. C., Gill, R., Brass, D. et al. 2016. Smothering in UK free-range flocks. Part 2: investigating correlations between disease, housing and management practices. Veterinary Record 179(10), 252.

Smothering, when birds group together in a way that results in death from suffocation, is a welfare and economic concern for the egg industry. This questionnaire-based study explored correlations between disease, housing, management practices and...

Hartcher, K. M., Tran, M. K. T. N., Wilkinson, S. J., et al. 2015. Plumage damage in free-range laying hens: Behavioural characteristics in the rearing period and the effects of environmental enrichment and beak-trimming. Applied Animal Behaviour Science 164, 64-72.

Severe feather-pecking, whereby birds peck at and pull out the feathers of other birds, is one of the greatest welfare concerns and the most prevalent behavioural problem in laying hens. It can be extremely difficult...

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...

Adamson, T. W., Perez, M.C. 2014. Use of cuttlebones to reduce the incidence of feather pecking in chickens. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 540 (Abstract #PS56).

Feather pecking is a maladaptive behavior where chickens (and other poultry species) peck the feathers of conspecifics and damage the plumage and frequently the skin. It is one of the most common behavioral problems in...

Daigle, C. L., Rodenburg, T. B., Bolhuis, J. E. et al. 2014. Use of dynamic and rewarding environmental enrichment to alleviate feather pecking in non-cage laying hens. Applied Animal Behaviour Science 161, 75-85.

Feather pecking (FP) can cause feather loss, resulting in physical injuries, which may lead to cannibalism. FP appears to be a redirection of foraging behavior, which intensifies when hens have difficulty coping with stress and...

Alworth, L. C., Buerkle, S. C. 2013. The effects of music on animal physiology, behavior and welfare. Lab Animal 42(2), 54-61.

Physiological and psychological effects of listening to music have been documented in humans. The changes in physiology, cognition and brain chemistry and morphology induced by music have been studied in animal models, providing evidence that...

Dixon, L. M., Duncan, I. J. H., Mason, G. J. 2010. The effects of four types of enrichment on feather-pecking behaviour in laying hens housed in barren environments. Animal Welfare 19(4), 429-435.

Severe feather pecking, a potentially stereotypic behaviour in chickens (Gallus gallus), can be reduced by providing enrichment. However, there is little comparative information available on the effectiveness of different types of enrichment. Providing forages to...

Brown, C. 2010. Organic wheatgrass as environmental enrichment. Lab Animal 39(3), 74-75.

Environmental enrichment must be provided for the various animal species that are housed in laboratory animal facilities. Wheatgrass can be used as a natural form of enrichment that requires minimal preparation and effort. Wheatgrass is...

Colson, S., Arnould, C., Michel, V. 2007. Motivation to dust-bathe of laying hens housed in cages and in aviaries. Animal 1(3), 433-437.

New housing systems for commercial egg production, furnished cages and non-cage systems, should improve the welfare of laying hens. In particular, thanks to the presence of a litter area, these new housing systems are thought...