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. 
Grippo, A. J., Ihm, E., Wardwell, J. et al. 2014. The effects of environmental enrichment on depressive and anxiety-relevant behaviors in socially isolated prairie voles. Psychosomatic Medicine 76(4), 277-284.

Social isolation is associated with depression, anxiety and negative health outcomes. Environmental enrichment, including environmental and cognitive stimulation with inanimate objects and opportunities for physical exercise, may be an effective strategy to include in treatment...

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...

Krügel, U., Fischer, J., Bauer, K. et al. 2014. The impact of social isolation on immunological parameters in rats. Archives of Toxicology 88(3), 853-855.

In various toxicological studies, single housing of rodents is preferred to standardize for regulatory purposes. However, housing conditions can have severe, often underestimated, impact on results in toxicological examinations. As different husbandry conditions have been...

Kulesskaya, N., Karpova, N. N., Ma, L. et al. 2014. Mixed housing with DBA/2 mice induces stress in C57BL/6 mice: Implications for interventions based on social enrichment. Frontiers in Behavioral Neuroscience 8, 257.

Several behavioral interventions, based on social enrichment and observational learning are applied in treatment of neuropsychiatric disorders. However, the mechanism of such modulatory effect and the safety of applied methods on individuals involved in social...

Monteiro, B. M., Moreira, F. A., Massensini, A. R. et al. 2014. Enriched environment increases neurogenesis and improves social memory persistence in socially isolated adult mice. Hippocampus 24(2), 239-248.

Social memory consists of the information necessary to identify and recognize cospecifics and is essential to many forms of social interaction. Social memory persistence is strongly modulated by the animal's experiences. We have shown in...

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...

Turner, P. V., Sunohara-Neilson, J., Ovari, J. et al. 2014. Effects of single compared with pair housing on hypothalamic-pituitary-adrenal axis activation and low-dose heroin place conditioning in adult male Sprague-Dawley rats. JAALAS 53(2), 161-167.

Whether social isolation of adult rats under standard laboratory conditions produces significant long-term alterations in behavior and physiology is unclear. In the present study, male Sprague–Dawley rats were singly or paired-housed for 10 wk. During...

Vaughan, L. M., Dawson, J. S., Porter, P. R. et al. 2014. Castration promotes welfare in group-housed male Swiss outbred mice maintained in educational institutions. JAALAS 53(1), 38-43.

Educational institutions maintain group-housed mice of both sexes for training veterinarians and technicians in husbandry, medication, and sampling procedures. Mice kept in all-male groups may experience poor welfare due to fighting. Castrated mice may be...

Verma, R., Friedler, B. D., Harris, N. M. et al. 2014. Pair housing reverses post-stroke depressive behavior in mice. Behavioural Brain Research 269, 155-163.

Social isolation (SI) has been linked epidemiologically to high rates of morbidity and mortality following stroke. In contrast, strong social support enhances recovery and lowers stroke recurrence. However, the mechanism by which social support influences...

O'Connor, A. M., Burton, T. J., Leamey, C. A. et al. 2014. The use of the puzzle box as a means of assessing the efficacy of environmental enrichment. JoVE (Journal of Visualized Experiments) 94, e52225.

Environmental enrichment can dramatically influence the development and function of neural circuits. Further, enrichment has been shown to successfully delay the onset of symptoms in models of Huntington's disease, suggesting environmental factors can evoke a...

Rock, M. L., Rodriguez, K., Karas, A. Z. et al. 2014. The time-to-integrate-to-nest test as an indicator of wellbeing in laboratory mice. JAALAS 53(1), 24-28.

Minimizing and alleviating pain and distress in laboratory mice without compromising the methodologic integrity of research is a crucial goal. However, current methods for welfare assessment in mice are not well suited to cageside checks...

Rock, M. L., Karas, A. Z., Gallo, M. S. et al. 2014. Housing condition and nesting experience do not affect the time to integrate to nest test (TINT). Animal Welfare 23(4), 381-385.

Managing and assessing well-being in laboratory mice (Mus musculus) is both challenging and necessary. Assessments intended to detect negative welfare states in mice are usually performed via observation of animals in the home cage, but...

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...

Hawkins, P. 2014. Refining housing, husbandry and care for animals used in studies involving biotelemetry. Animals 4(2), 361-373.

Biotelemetry can contribute towards reducing animal numbers and suffering in disciplines including physiology, pharmacology and behavioural research. However, the technique can also cause harm to animals, making biotelemetry a ‘refinement that needs refining’. Current welfare...

Spangenberg, E., Wallenbeck, A., Eklöf, A.-C. et al. 2014. Housing breeding mice in three different IVC systems: Maternal performance and pup development. Laboratory Animals 48(3), 193–206.

A proper cage environment is essential for the welfare of laboratory mice, especially for females during the energy demanding lactation period and for pups during early development and growth. The most common housing system for...

Jones, C. E., Riha, P. D., Gore, A. C. et al. 2014. Social transmission of Pavlovian fear: Fear-conditioning by-proxy in related female rats. Animal Cognition 17(3), 827–834.

Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a foot-shock) leads to associative learning such that the tone alone will elicit a conditioned response (e.g., freezing)...

Melotti, L., Bailoo, J., Murphy, E. et al. 2014. Play in rats: Association across contexts and types, and analysis of structure. Animal Behavior and Cognition 1(4), 489–501.

Play has been proposed as a promising indicator of positive animal welfare. We aimed to study play in rats across contexts (conspecific/heterospecific) and types (social: pinning, being pinned; solitary: scampering), and we investigated its structure...

Yuki, S., Okanoya, K. 2014. Behavioral correlates of 50-kHz ultrasonic vocalizations in rats: Progressive operant discrimination learning reduces frequency modulation and increases overall amplitude. Animal Behavior and Cognition 1(4), 452–463.

Ultrasonic vocalizations (USVs) in rats are thought to contain ecological signals reflecting emotional states. These USVs are centered on 50-kHz, and frequency modulation (FM) is hypothesized to indicate positive emotion; however, results from recent studies...

Makowska, I. J., Weary, D. M. 2013. Assessing the emotions of laboratory rats. Applied Animal Behaviour Science 148, 1-12.

Rats are one of the most commonly used species in research, and decades of testing have yielded a large amount of information pertaining to their experience of emotion. The aim of this review is to...

Annas, A., Bengtsson, C., Tornqvist, E. 2013. Group housing of male CD1 mice: Reflections from toxicity studies. Laboratory Animals 47(2), 127-129.

Owing to their naturally aggressive behaviour, male mice are often housed individually in toxicity studies. However, several publications advocate group-housing of mice to enable normal social behaviour and interactions between the animals. This refinement project...

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...

Posadas, M., Neubauer, T., Buckmaster, C. A. 2013. Noisy construction does not have to generate noisy data. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 670-671 (Abstract).

Our institution opened the Jan and Dan Duncan Neurologic Research Institute (NRI) in November of 2010. This facility houses a team of world renowned researchers working with mice and rats to develop treatments for childhood...

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...

Winnicker, C. 2013. Challenges and opportunities of implementing EU standards for social housing of rodents. Enrichment Record 15, 3-4.

The EU Directive on the protection of animals used for scientific purposes specifically states: Animals, except those which are naturally solitary, shall be socially housed in stable groups of compatible individuals. Even in cases where...