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. 
Shams, S., Chatterjee, D., Gerlai, R. 2015. Chronic social isolation affects thigmotaxis and whole-brain serotonin levels in adult zebrafish. Behavioral Brain Research 292, 283-87.

The popularity of the zebrafish has been growing in behavioral brain research. Previously utilized mainly in developmental biology and genetics, the zebrafish has turned out to possess a complex behavioral repertoire. For example, it is...

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...

Stuart, S., Robinson, E. S. J. 2015. Reducing the stress of drug administration: Implications for the 3Rs. Scientific Reports 5, 14288.

Restraint in animals is known to cause stress but is used during almost all scientific procedures in rodents, representing a major welfare and scientific issue. Administration of substances, a key part of most scientific procedures...

Bode, A. E., Barber, H. 2014. Use of vinyl nonadhesive tape as an alternative for positioning rodents in small animal imaging. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 597-598. (Abstract #P185).

Specific positioning for different imaging modalities is essential in our small animal imaging core. While we have different animal holders designed to position the animal inside the MRI, additional securing of the animal to the...

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...

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...

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...

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...

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...

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...

Cloutier, S., Baker, C., Wahl, K. et al. 2013. Playful handling as social enrichment for individually- and group-housed laboratory rats. Applied Animal Behaviour Science 143(2-4), 85-95.

Social housing is recommended for laboratory rats because they are highly social mammals but research constraints or medical issues often demand individual housing and, when social housing is practiced, it typically involves housing with only...

Wong, D., Makowska, I. J., Weary, D. M. 2013. Rat aversion to isoflurane versus carbon dioxide. Biology Letters 9(1), 20121000.

Some experts suggest that sedation of laboratory rodents with isoflurane before euthanasia with carbon dioxide (CO2) is a humane alternative to euthanasia with CO2 alone, but little research has compared aversion with these agents. Albino...

Chisholm, J., De Rantere D., Fernandez, N. J. et al. 2013. Carbon dioxide, but not isoflurane, elicits ultrasonic vocalizations in female rats. Laboratory Animals 47(4), 324-7.

Gradual filling of a chamber with carbon dioxide is currently listed by the Canadian Council on Animal Care guidelines as a conditionally acceptable method of euthanasia for rats. Behavioural evidence suggests, however, that exposure to...

Hosey, G., Melfi, V. 2012. Human-animal bonds between zoo professionals and the animals in their care. Zoo Biology 31(1), 13-26.

Some human-animal relationships can be so positive that they confer emotional well-being to both partners and can thus be viewed as bonds. In this study, 130 delegates at zoo research and training events completed questionnaires...

Costa, R., Tamascia, M. L., Nogueira, M. D. et al. 2012. Handling of adolescent rats improves learning and memory and decreases anxiety. JAALAS 51(5), 548-553.

Some environmental interventions can result in physiologic and behavioral changes in laboratory animals. In this context, the handling of adolescent or adult rodents has been reported to influence exploratory behavior and emotionality. Here we examined...

Cloutier, S., Panksepp, J., Newberry, R. C. 2012. Playful handling by caretakers reduces fear of humans in the laboratory rat. Applied Animal Behaviour Science 140(3-4), 161-171.

Handling of laboratory rats can increase physiological and emotional stress, leading to a fearful relationship with humans. We hypothesized that the affective quality of handling techniques used during routine care influences the animals' fear of...

Gudsnuk, K., Champagne, F. A. 2012. Epigenetic influence of stress and social environment. ILAR Journal 53(3-4), 279-288.

Animal models of early-life stress and variation in social experience across the lifespan have contributed significantly to our understanding of the environmental regulation of the developing brain. Plasticity in neurobiological pathways regulating stress responsivity, cognition...

Parker, M. O., Millington, M. E., Combe, F. J. et al. 2012. Housing conditions differentially affect physiological and behavioural stress responses of zebrafish, as well as the response to anxiolytics. PLOS ONE 7(4), e34992.

Zebrafish are a widely utilised animal model in developmental genetics, and owing to recent advances in our understanding of zebrafish behaviour, their utility as a comparative model in behavioural neuroscience is beginning to be realised...

Azar, T., Sharp, J., Lawson, D. 2011. Heart rates of male and female Sprague-Dawley and spontaneously hypertensive rats housed singly or in groups. JAALAS 50(2), 75-84.

This study was conducted to confirm our previous reports that group housing lowered basal heart rate and various evoked heart-rate responses in Sprague-Dawley male and female rats and to extend these observations to spontaneously hypertensive...

Nakayasu, T., Kato, K. 2011. Is full physical contact necessary for buffering effects of pair housing on social stress in rats? Behavioural Processes 86(2), 230-235.

Our previous study showed that pair housing with a familiar male prevented an increase in anxiety caused by social defeat in male rats. The present study attempted to identify the aspects of social interactions with...

Claxton, A. M. 2011. The potential of the human-animal relationship as an environmental enrichment for the welfare of zoo-housed animals. Applied Animal Behaviour Science 133(1), 1-10.

Environmental enrichment strategies are used to improve both the physiological and psychological welfare of captive animals, which can be achieved by increasing the expression of natural behaviour and decreasing abnormal behaviours. Examples of successful environmental...

Baran, S. W., Froberg-Fejko, K., Lecker, J. et al. 2010. Post-surgical environmental enrichment in rodents. Enrichment Record 3, 4-6.

Environmental enrichment is a key component of rodent animal welfare since it influences the animal’s overall well-being, provides opportunities for activity, and encourages rodent appropriate behaviors. Many aspects of rodent enrichment have received a significant...

Turner, P. V., Ovari, J., Pinelli, C. et al. 2010. Long-term effects of housing and enrichment on affective behavior and responsiveness of Sprague-Dawley rats. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 658-659 (Abstract #PS12).

Most rodent studies evaluate different caging paradigms over short periods of time, which may not be realistic for typical colony settings. Inappropriate housing may lead to boredom, aggression, stereotypies, and altered metabolism, which in turn...