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. 
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...

Rushen, J., de Passillé, A. M., Appleby, M. C. et al. 2014. Alone or together: A risk assessment approach to group housing. In: Dilemmas in Animal Welfare. Appleby, M. C., Weary, D. M., Sandøe, P. (eds), 169-187. CAB International, Oxfordshire, UK.

The question of whether it is better to house animals in groups rather than alone deals with the unresolved issues at the heart of animal welfare. In particular, we need to be able to rank...

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...

Bergman, T. J., Sheehan, M. J. 2013. Social knowledge and signal in primates. American Journal of Primatology 75(7), 683-694.

Primates are notable for having a rich and detailed understanding of their social environment and there has been great interest in the evolution and function of social knowledge in primates. Indeed, primates have been shown...

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...

Camacho, J. N., Boskovic, S., Moeller, E. 2012. Improved nonhuman primate social housing using visual cues associated for an intensive research study. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 636-637 (Abstract #PS35).

Lean management-based visual tools have been used to improve the quality of animal care associated with a complex research study involving immune-compromised cynomolgus monkeys (M. fascicularis) in various postsurgical recovery states. In order to effectively...

Baker, K. C. 2012. Implementation of pair housing for laboratory primates. American Journal of Primatology 74(S1), 31. (35th Meeting of the American Society of Primatologists Scientific Program, Abstract #20)

There is a general consensus among those studying the welfare of captive primates that social housing is the most effective means for promoting psychological well-being. It is well established that socially-housed rhesus macaques (Macaca mulatta)...

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...

Schapiro, S. J., Bernacky, B. J. 2011. Socialization strategies and disease transmission in captive colonies of nonhuman primates. American Journal of Primatology 74(6), 518-527.

In captive research environments for nonhuman primates (NHP), social housing strategies are often in conflict with protocols designed to minimize disease transmission. This is particularly true in breeding colonies, and is especially relevant when attempting...

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...

Mathieu, C. 2011. Comparative analysis of blood sampling techniques in the rat. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 738 (Abstract #PS81).

Blood sampling is one of the most common procedures performed on laboratory animals as part of scientific research. As an ongoing commitment, our institution has identified a need to improve the current blood sampling method...

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...

Cloutier, S., Wahl, K., Newberry, R. C. 2010. Playful handling mitigates the stressfulness of injections in laboratory rats. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 721 (Abstract #P126).

Rats can be playfully handled (tickled) in a manner that mimics playful social contact with conspecifics. We hypothesized that the timing of tickling in relation to an intraperitoneal injection would affect the efficacy of tickling...

Gonder, J. C., Laber, K. 2007. A renewed look at laboratory rodent housing and management. ILAR Journal 48(1), 29-46.

In this article, recent publications are examined to determine the potential impact of new scientific evidence on current practices for the housing and care of laboratory rodents. The discussion points out recent advances in technology...

Van Loo, P., Skoumbourdis, E., Reinhardt, V. 2006. Postsurgical pairing: A discussion by the Refinement & Enrichment Forum. Animal Technology and Welfare 5(1), 17-19.

Our experience-based discussion suggests that social animals benefit from compatible companionship during post-operative recovery. The traditional practice of keeping animals alone in an unfamiliar environment after surgery increases the subjects surgery-associated stress. Providing a familiar...

Lutz, C. K., Novak, M. 2005. Environmental enrichment for nonhuman primates: Theory and application. ILAR Journal 46(2), 178-191.

Only social contact satisfies the goal of promoting a wide variety of species-typical activities while at the same time reducing or preventing the development of abnormal behavior... A number of toys should be provided initially...

Kulpa-Eddy, J. A., Taylor, S., Adams, K. M. 2005. USDA perspectives on environmental enrichment for animals. ILAR Journal 46(2), 83-94.

This article provides a brief historical background of the events and circumstances that led to the 1985 Animal Welfare Act (AWA) amendments. It describes the development of the regulations promulgated by the US Department of...

Luzzi, M., Skoumbourdis, E., Baumans, V. et al. 2005. Collecting blood from rodents: A discussion by the Laboratory Animal Refinement and Enrichment Forum. Animal Technology and Welfare 4, 99-102.

The question was asked: "In your own experience, what is the least disturbing technique - from the subject's point of view! - of blood collection for rodents?" In summary, it is fair to conclude the...

Bayne, K. 2005. Potential for unintended consequences of environmental enrihment for laboratory animals and research results. ILAR Journal 46(2), 129-139.

Many aspects of the research animal's housing environment are controlled for quality and/or standardization. Of recent interest is the potential for environmental enrichment to have unexpected consequences such as unintended harm to the animal, or...