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. 
Zobel, G., Neave, H., Henderson, H. et al. 2017. Calves use an automated brush and a hanging rope when pair-housed. Animals 7(11), 84.

Calf housing often only meets the basic needs of calves, but there is a growing interest in providing enrichments. This study described the behaviour of calves when they were given the opportunity to interact with...

Billingham, E. 2017. The curious tale of axolotl enrichment. Animal Technology and Welfare 16(3), 191-194.

Axolotls can be used in scientific research to provide fertilised embryos for investigations into the genetic pathways controlling stem cell development. Breeding animals are housed for several years and environmental enrichment is required to improve...

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...

Girard, T. E, Zuidhof, M. J., Bench, C. J. 2017. Feeding, foraging, and feather pecking behaviours in precision-fed and skip-a-day-fed broiler breeder pullets. Applied Animal Behaviour Science 188, 42-49.

Broiler breeder chickens are feed-restricted to control growth and maximize chick production. Feed restriction creates welfare concerns as conventional skip-a-day feeding can increase activity levels and oral stereotypies during the rearing period. A precision feeding...

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...

Mandel, R., Nicol, C. J. 2017. Re-direction of maternal behaviour in dairy cows. Applied Animal Behaviour Science 195, 24-31.

In the milk producing industry, most aspects of maternal behaviour are discouraged, but milk production is actively maintained in the absence of the calf. The process of milk let down, is mediated, at least partly...

Horvath, K., Fernandez, M., Miller-Cushon, E. K. 2017. The effect of feeding enrichment in the milk-feeding stage on the cognition of dairy calves in a T-maze. Applied Animal Behaviour Science 187, 8-14.

In many species, environmental complexity is known to affect cognitive development, yet it is common to house dairy calves individually in restrictive environments. The hypothesis of this study was that providing calves with simple nutritional...

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...

Knapek, K. J., Adams, M. K., Ayers, J. D. 2017. What’s in our chamber of secrets? Python housing in a laboratory setting. Laboratory Animal Science Professional 5(4) (December), 16-19.

At Colorado State University we have an investigator who requested care for 2 different species of pythons, the green tree python (Morelia viridis) and the ball python (Python reguis), to study the pathology of an...

Foditsch, C., Oikonomou, G., Machado, V. S. et al. 2016. Lameness prevalence and risk factors in large dairy farms in upstate New York. Model development for the prediction of claw horn disruption lesions. PLOS ONE 11(1), e0146718.

The main objectives of this prospective cohort study were a) to describe lameness prevalence at drying off in large high producing New York State herds based on visual locomotion score (VLS) and identify potential cow...

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...

Johannson, S. G., Raginski, C., Schwean-Lardner, K. et al. 2016. Providing laying hens in group-housed enriched cages with access to barley silage reduces aggressive and feather-pecking behaviour. Canadian Journal of Animal Science 96(2), 161-171.

Two trials were conducted to study the effect of feeding barley silage on the behaviour and performance of beak-trimmed laying hens. In each trial, 20 hens and 2 roosters were housed in each of eight...

Kieffer, J. 2016. The scratch factor – Using free, recycled street sweeping brooms as enrichment devices for cattle. Laboratory Animal Science Professional 4(1) (March), 33-36.

There is an increasing amount of consideration being paid to cattle welfare and enrichment, both at agricultural research institutions and via welfare audits on commercial operations. A crucial element of these welfare and enrichment evaluations...

Winnicker, C., Gaskill, B., Garner, J. P. et al. 2016. A Guide to the Behavior & Enrichment of Laboratory Rodents. Charles River Laboratories.

Covering species-typical behavior as well as abnormal/malfunctional behavior and stereotypes observed in mice, rats, hamsters and gerbils, this is an excellent resource for those looking to implement or enhance an existing behavioral husbandry and enrichment...

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...

Bethell, E. J., Koyama, N. F. 2015. Happy hamsters? Enrichment induces positive judgement bias for mildly (but not truly) ambiguous cues to reward and punishment in Mesocricetus auratus. Royal Society Open Science 2, 140399.

Recent developments in the study of animal cognition and emotion have resulted in the ‘judgement bias’ model of animal welfare. Judgement biases describe the way in which changes in affective state are characterized by changes...

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...