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. 
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...

Morano, R., Hoskins, O., Smith, B. L. et al. 2019. Loss of environmental enrichment elicits behavioral and physiological dysregulation in female rats. Frontiers in Behavioral Neuroscience 12, 287.

Chronic stress drives behavioral and physiological changes associated with numerous psychiatric disease states. In rodents, the vast majority of chronic stress models involve imposition of external stressors, whereas in humans stress is often driven by...

Makowska, I. J., Weary, D. M. 2019. A good life for laboratory rodents? ILAR Journal 60(3), 373-388.

Most would agree that animals in research should be spared “unnecessary” harm, pain, or distress, and there is also growing interest in providing animals with some form of environmental enrichment. But is this the standard...

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...

Clarke, D., Ioannou, L. 2018. Introduction of gang caging for group housed rats. Animal Technology and Welfare 17(2), 136-137.

Using an existing gang cage designed for ferrets, we developed a version that would be suitable for housing rats. Caging consisted of 3 floors with a combined floor area of 11620m, connected by 2 ladders...

Sikora, M., Nicolas, C., Istin, M. et al. 2018. Generalization of effects of environmental enrichment on seeking for different classes of drugs of abuse. Behavioural Brain Research 341, 109-113.

Background: Addiction is a chronic disease characterized by persistent vulnerability to relapse during abstinence. In animal models of addiction, accumulating evidence suggests that exposure to environmental enrichment (EE) during periods of abstinence can have curative...

Wang, R., Hausknechta, K. A., Haj-Dahmane, S. et al. 2018. Decreased environmental complexity during development impairs habituation of reinforcer effectiveness of sensory stimuli. Behavioural Brain Research 337, 53-60.

Previous research has shown that rats reared in simple/impoverished environments demonstrate greater repetitive responding for sensory reinforcers (e.g., light onset). Moreover, the brains of these rats are abnormally developed, compared to brains of rats reared...

Sparling, J. E., Baker, S. L., Bielajew, C. 2018. Effects of combined pre- and post-natal enrichment on anxiety-like, social, and cognitive behaviours in juvenile and adult rat offspring. Behavioural Brain Research 353, 40-50.

The pre- and post-natal periods are characterized by unrivalled growth and are sensitive to environmental changes. A correctly stimulating early environment is essential for developing natural behaviors and maintaining affective wellness. Five litters of rat...

Perdue, B. M., Beran, M. J., Washburn, D. A. 2018. A computerized testing system for primates: Cognition, welfare, and the Rumbaughx. Behavioural Processes 156, 37-50.

Innovations in apparatus technology come about for a variety of reasons such as the need to use the same methodology with various species, the opportunity to present dynamic and carefully controlled stimuli, the goal of...

Hankenson, F. C., Marx, J. O., Gordon, C. J. et al. 2018. Effects of rodent thermoregulation on animal models in the research environment. Comparative Medicine 68(6), 425–438.

To best promote animal wellbeing and the efficacy of biomedical models, scientific, husbandry, and veterinary professionals must consider the mechanisms, influences, and outcomes of rodent thermoregulation in contemporary research environments. Over the last 2 decades...

Heyworth, C., Olivo, D. 2018. Environmental and psychological enrichment for NHPs reimagined and repurposed. Laboratory Animal Science Professional 5(4) (December), 39-43.

This article describes creative enrichment ideas for nonhuman primates, including celery stalks embedded with seeds; paper rolled into tubes, braided and filled with fruit and seeds; pineapple crowns loaded with treats; dry spaghetti noodles coated...

French, F., Mancini, C., Sharp, H. 2018. High tech cognitive and acoustic enrichment for captive elephants. Journal of Neuroscience Methods 300, 173-183.

This paper investigates the potential for using technology to support the development of sensory and cognitive enrichment activities for captive elephants. It explores the usefulness of applying conceptual frameworks from interaction design and game design...

Castelhano-Carlos, M. J., Baumans, V., Sousa, N. 2017. PhenoWorld: Addressing animal welfare in a new paradigm to house and assess rat behaviour. Laboratory Animals 51(1), 36-43.

The use of animals is essential in biomedical research. The laboratory environment where the animals are housed has a major impact on them throughout their lives and influences the outcome of animal experiments. Therefore, there...

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...

Palmer, S. 2017. Rescue-Enrich-Release: The environmental enrichment program for three species of captive primates at Colobus. Canopy 17(2), 27-30.

It is widely known that the psychological wellbeing of captive animals can become compromised by a captive environment that lacks proper environmental stimulation. Environmental enrichment programs have become the norm in captive environments yet research...

Alligood, C. A., Dorey, N. R., Mehrkam, L. R. et al. 2017. Applying behavior-analytic methodology to the science and practice of environmental enrichment in zoos and aquariums. Zoo Biology 36(3), 175–185.

Environmental enrichment in zoos and aquariums is often evaluated at two overlapping levels: published research and day‐to‐day institutional record keeping. Several authors have discussed ongoing challenges with small sample sizes in between‐groups zoological research and...

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...

Carlson, A., Allen, C., Skoumbourdis, E. et al. 2017. Cooked food for non-human primates: A discussion by the Laboratory Animal Refinement & Enrichment Forum. Animal Technology and Welfare 16(2), 124-126.

"Do any of you give cooked food like pasta, potatoes or vegetables to non-human primates? What’s your experience? Do the animals benefit from cooked food; do they like it; does it affect their health in...

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)...

Coleman, K., Novak, M. A. 2017. Environmental enrichment in the 21st century. ILAR Journal 58(2), 295-307.

More than a quarter of a century has elapsed since the Animal Welfare Act mandated that research facilities develop and follow a plan to promote the psychological well-being of captive primates. Since passage of this...

Sands, C., Evans, C., Buckmaster, C. A. 2017. The grooming sleeve: Encouraging conspecific-like behavior and strengthening the human-animal bond. Laboratory Animal Science Professional 5(2) (June), 52-53.

The act of grooming has been found to greatly decrease stress, heart rate, and cortisol levels in nonhuman primates; this decrease in stress and cortisol is seen in the animal being groomed, as well as...

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...