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. 
Pinelli, C., Leri, F., Turner, P. 2017. Long term physiologic and behavioural effects of housing density and environmental resource provision for adult male and female Sprague Dawley rats. Animals 7(6), 44.

There is considerable interest in refining laboratory rodent environments to promote animal well-being, as well as research reproducibility. Few studies have evaluated the long term impact of enhancing rodent environments with resources and additional cagemates...

Brenneis, C., Westhof, A., Holschbach, J. et al. 2017. Automated tracking of motion and body weight for objective monitoring of rats in colony housing. JAALAS 56(1), 18-31.

Living together in large social communities within an enriched environment stimulates self-motivated activity in rats. We developed a modular housing system in which a single unit can accommodate as many as 48 rats and contains...

Simpson, D. 2017. Investigation of transportation on rat acclimatisation using novel cage side recording equipment (Rodent Big Brother). Animal Technology and Welfare 16(1), 1-12.

The transportation of animals from supplier to experimental facility is one of the biggest stressors to animals in research. Transportation unavoidably causes stress and when the animals arrive at the testing facility they require a...

Kleefeld, S., Bannerton, K., Kelly, J.2017. Effect of moderate environmental enrichment on commonly used behavioural tests in rats. Animal Technology and Welfare 16(1), 75-76.

The environment that laboratory animals are housed in should reflect their natural habitats in a manner that can satisfy their innate physiological and behavioural needs. This includes nest building, hiding, exploring and foraging. Providing environmental...

Jones, T., Robinson, M., Leach, M. et al. 2017. Ultrasonic vocalisation as a measure of positive welfare in rats. Animal Technology and Welfare 16(2), 127-129.

Studies of animal welfare in laboratory animals have historically relied on the measurement of negative indicators rather than the assessment of positive indicators of welfare. Practical methods of welfare assessment are required to allow refinement...

Mármol, F., Sánchez, J., Torres, M. N. et al. 2017. Environmental enrichment in the absence of wheel running produces beneficial behavioural and anti-oxidative effects in rats. Behavioural Processes 144, 66-71.

The effects of early environmental enrichment (EE) when solving a simple spatial task in adult male rats were assessed. After weaning, rats were housed in pairs in enriched or standard cages (EE and control groups)...

Danner, L., Rao, V. P. 2017. Should rat enrichment devices be used beyond a month? Laboratory Animal Science Professional 5(1) (March), 41-43.

Enrichment devices made of materials such as nylon and wood are common gnawing devices used in animal facilities. In most institutions, these devices are used for a limited period and then discarded. At Pfizer, enrichment...

Rossi, N. 2017. The other 3Rs: Reduce, reuse, and recycle for rodents. Laboratory Animal Science Professional 5(1) (March), 44-46.

Since funding can be scarce, I seek novel and economical ways to promote the psychological wellbeing of the animals through environmental enrichment and allow research animals to express species-specific behaviors and control their environment to...

Smith, B. L., Lyons, C. E., Correa, F. G. et al. 2017. Behavioral and physiological consequences of enrichment loss in rats. Psychoneuroendocrinology 77, 37-46.

Significant loss produces the highest degree of stress and compromised well-being in humans. Current rodent models of stress involve the application of physically or psychologically aversive stimuli, but do not address the concept of loss...

Li, K. A., Lund, E. T., Voigt, J.W. 2016. The impact of early postnatal environmental enrichment on maternal care and offspring behaviour following weaning. Behavioural Processes 122, 51-58.

The early postnatal period is a sensitive period in rodents as behavioural systems are developing and maturing during this time. However, relatively little information is available about the impact of environmental enrichment on offspring behaviour...

Makowska, I. J., Weary, D. M. 2016. Differences in anticipatory behaviour between rats (Rattus norvegicus) housed in standard versus semi-naturalistic laboratory environments. PLOS ONE 11(1), e0147595.

Laboratory rats are usually kept in relatively small cages, but research has shown that they prefer larger and more complex environments. The physiological, neurological and health effects of standard laboratory housing are well established, but...

Makowska, I. J., Weary, D. M. 2016. The importance of burrowing, climbing and standing upright for laboratory rats. Royal Society Open Science 3, 160136.

Standard laboratory cages prevent rats (Rattus norvegicus) from performing many behaviours that they perform in the wild, but little is known about how this may affect their welfare. The aims of this study were (i)...

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...

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...

Heyse, N. C., Brenes, J. C., Schwarting, R. K. W. 2015. Exercise reward induces appetitive 50-kHz calls in rats. Physiology & Behavior 147, 131-140.

Rats express affective states by visible behaviors (like approach or flight) and through different kinds of ultrasonic vocalizations (USV). 50-kHz calls are thought to reflect positive affective states since they occur during rewarding situations like...

Qi, K., De-mi, S., Chuan, Q. 2014. Current understanding and use of environmental enrichment in China. Enrichment Record 20, 8-11.

In practice, consideration is given to providing most of the species used in research,testing and education withsome level of environmental enrichment. However, although the current level of awareness and understanding about the benefits of environmental...

Lidfors, L., Wichman, A., Ewaldsson, B. et al. 2014. Enriched cages for groups of laboratory male rats and their effects on behaviour, weight gain and adrenal glands. Laboratory Animals 48, 36-49.

We investigated if there were any negative effects on the behaviour and physiology of rats housed in groups of five in two types of enriched cages and compared them with paired-housed rats housed in traditional...

Escribano, B., Quero, I., Feijóo, M. et al. 2014. Role of noise and music as anxiety modulators: Relationship with ovarian hormones in the rat. Applied Animal Behaviour Science 152, 73-82.

This work aims to verify the role of noise and music as anxiety modulators and their relationship with ovarian hormones. For this purpose, female Wistar rats were used and treated, forming different experimental groups, with...

Ditewig, A. C., Bratcher, N. A., Davila, D. R. et al. 2014. Enrichment with wood blocks does not affect toxicity assessment in an exploratory toxicology model using Sprague-Dawley rats. JAALAS 53(3), 246-260.

Environmental enrichment in rodents may improve animal well-being but can affect neurologic development, immune system function, and aging. We tested the hypothesis that wood block enrichment affects the interpretation of traditional and transcriptomic endpoints in...

Hori, M., Yamada, K., Ohnishi, J. et al. 2014. Tickling during adolescence alters fear-related and cognitive behaviors in rats after prolonged isolation. Physiology & Behavior 131, 62-67.

Social interactions during adolescence are important especially for neuronal development and behavior. We recently showed that positive emotions induced by repeated tickling could modulate fear-related behaviors and sympatho-adrenal stress responses. In the present study, we...

Sharp, J., Azar, T., Lawson, D. 2014. Effects of a complex housing environment on heart rate and blood pressure of rats at rest and after stressful challenges. JAALAS 53(1), 52-60.

Housing enrichment for rodents continues to be a discussion topic within the animal care community. The objective of this study was to determine the extent to which a complex housing environment affects heart rate, blood...

Abou-Ismail, U. A., Darwish, R. A., Ramadan, S. G. A. 2014. Should cages of laboratory rats be enriched physically or socially? Global Veterinaria 13(4), 570-582.

Experiments of environmental enrichment usually compare between group-housed rats in enriched and unenriched cages or between group-housed rats in enriched cages and single-housed rats in unenriched cages. This bias is mainly to maximize the chance...

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...

Reinhardt, V. (ed.) 2013. Compassion Makes a Difference - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume III. Animal Welfare Institute, Washington, DC.

This is the third volume of discussions that took place on the Laboratory Animal Refinement & Enrichment Forum (LAREF). This forum is dedicated to the exchange of personal experiences of refining the conditions under which...

Wren, M. A., Dauchy, R. T., Hill, S. M. et al. 2013. Colored enrichment devices influence behavior and circadian metabolism and physiology in Sprague-Dawley rats. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 608 (Abstract #PS2).

Enrichment devices and strategies, as currently endorsed by the Guide, are used to improve laboratory animal health and wellbeing. Many conclusions supporting this premise, however, are based primarily on observational studies with minimal consideration for...