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. 
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...

Gaillard, C., Meagher, R. K., von Keyserlingk, M. A. et al. 2014. Social housing improves dairy calves' performance in two cognitive tests. PLOS ONE 9(2), e90205.

Early social housing is known to benefit cognitive development in laboratory animals. Pre-weaned dairy calves are typically separated from their dam immediately after birth and housed alone, but no work to date has addressed the...

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...

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...

Petak, I. 2013. Communication patterns within a group of shelter dogs and implications for their welfare. Journal of Applied Animal Welfare Science 16(2), 118-139.

Keeping shelter dogs in groups provides them with a more socially and physically enriched environment, but eventually it may cause them stress. Understanding dogs' communication could help shelter staff recognize and prevent undesirable communicative patterns...

Pullen, A. J., Merrill, R. J. N., Bradshaw, J. W. S. 2013. The effect of familiarity on behavior of kenneled dogs during interactions with conspecifics. Journal of Applied Animal Welfare Science 16(1), 64-76.

Kenneled environments often prevent direct physical contact between dogs, potentially causing stress, and so it has been recommended that such contact should be provided. This study examined the effect of familiarity on the behavior of...

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...

Sposato, M. 2013. Benefits of an enhanced enrichment program for a canine research colony. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 669 (Abstract #P176).

The overall benefits of an enrichment and exercise program for research canines has been well documented and is a required element, by the United States Department of Agriculture (USDA), of any institution’s Animal Care and...

Rose, A. M. 2013. An inexpensive approach to social housing enrichment for laboratory rabbits and guinea pigs. Laboratory Animal Science Professional 1(4) (December), 46-48.

We analyzed our current enrichment protocols in order to develop and implement social experiences for our rabbit and guinea pig colonies. This article describes the development of an exercise pen for rabbits and a custom-made...

Wolfensohn, S., Hawkins, P., Lilley, E. et al. 2013. Reducing suffering in experimental autoimmune encephalomyelitis (EAE). Journal of Pharmacological and Toxicological Methods 67(3), 169-176.

This report is based on discussions and submissions from an expert working group consisting of veterinarians, animal care staff and scientists with expert knowledge relevant to the field. It aims to facilitate the implementation of...

Wolfensohn, S., Hawkins, P., Lilley, E. et al. 2013. Reducing suffering in animal models and procedures involving seizures, convulsions and epilepsy. Journal of Pharmacological and Toxicological Methods 67(1), 9-15.

This report is based on discussions and submissions from an expert working group consisting of veterinarians, animal care staff and scientists with expert knowledge relevant to the field and aims to facilitate the implementation of...

Rault, J.-L. 2012. Friends with benefits: Social support and its relevance for farm animal welfare. Applied Animal Behaviour Science 136(1), 1-14.

Despite growing interest in promoting positive welfare, rather than just alleviating poor welfare, potential measures of good welfare, and means to provide it, have remained elusive. In humans social support improves stress-coping abilities, health, and...

Walters, S. L., Torres-Urbano, C. J., Chichester, L. et al. 2012. The impact of huts on physiological stress: A refinement in post-transport housing of male guinea pigs (Cavia porcellus). Laboratory Animals 46(3), 220-224.

The ideal animal model would contribute no confounding variables in experimental science. Variables affect experimental design resulting in increased animal use or repeated studies. We demonstrated a simple refinement which may reduce the number of...

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...

de Paula Vieira, A., Weary, D. M., de Passillé, A. M. 2012. Effects of the early social environment on behavioral responses of dairy calves to novel events. Journal of Dairy Science 95(9), 5149-5155.

Providing young animals the opportunity to engage in more complex social interactions is hypothesized to improve their capacity to cope with changing environments. To test the effects of the early social environment on the behavioral...

Duve, L. R., Jensen, M. B. 2012. Social behavior of young dairy calves housed with limited or full social contact with a peer. Journal of Dairy Science 95(10), 5936-5945.

This study compared the effect of individual and pair housing and age at pair housing on the social behavior of young dairy calves. Twenty-seven pairs of calves were reared from birth until 6 wk either...

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...