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. 
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...

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...

Riley, J. L., Noble, D. W. A., Byrne, R. W. et al. 2017. Does social environment influence learning ability in a family-living lizard? Animal Cognition 20(3), 449–458.

Early developmental environment can have profound effects on individual physiology, behaviour, and learning. In birds and mammals, social isolation during development is known to negatively affect learning ability; yet in other taxa, like reptiles, the...

Pinnell, R. C., Almajidy, R. K., Hofmann, U. G. 2016. Versatile 3-D printed headstage implant for group housing of rodents. Journal of Neuroscience Methods 257, 134-138.

An unfavourable yet necessary side-effect of stereotaxic surgery involves the social isolation of post-surgery rats, in order to protect their wound site or skull-mounted implant from damage. Social isolation can cause a myriad of behavioural...

Harl, H., Stevens, L., Margulis, S. W. et al. 2016. Gibbon aggression during introductions: An international survey. Journal of Applied Animal Welfare Science 19(3), 260-270.

Little is known regarding the prevalence of aggression seen during introductions of captive gibbons (Hylobatidae). In this study, an online survey was developed to quantify and collect contextual details regarding the frequency and types of...

Brien, M. L., Webb, G. J., McGuinness, K. A. et al. 2016. Effect of housing density on growth, agonistic behaviour, and activity in hatchling saltwater crocodiles (Crocodylus porosus). Applied Animal Behaviour Science 184, 141-149.

The purpose of this study was to examine the effect of density on growth rate, agonistic behaviour, activity and use of space by hatchling C. porosus in captivity. Hatchling C. porosus were raised in identical...

Cloutier, S., Wahl, K. L., Panksepp, J. et al. 2015. Playful handling of laboratory rats is more beneficial when applied before than after routine injections. Applied Animal Behaviour Science 164, 81-90.

The ability of positive affective states to counteract negative states engendered by routine medical procedures remains poorly studied. In laboratory rats, positive affect typically associated with rough-and-tumble play can be induced through human “hand play”...

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...

McCrossin, F. G. 2014. The effect of pair housing on the aye-aye (Daubentonia madagascariensis). American Journal of Primatology 76(S1), 54. (37th Meeting of the American Society of Primatologists Scientific Program, Abstract #52)

Aye-ayes (Daubentonia madagascariensis) are thought to be solitary animals and are often housed alone in captivity. However, for all primates sociality is known to play a major role in psychological well-being. Captive animals can develop...

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...

Shapiro, S. J., Reamer, L. A., Mareno, M. C. et al. 2014. Providing chimpanzees opportunities to voluntarily participate in their own care: Choice of medications. American Journal of Primatology 76(S1), 73 (37th Meeting of the American Society of Primatologists Scientific Program, Abstract #112).

Captivity often limits a primate’s ability to make meaningful choices on a daily basis. Effective captive (behavioral) management programs should provide primates with opportunities to make meaningful choices. In the present study, arthritic chimpanzees were...

van Leeuwen, E. J. C., Mulenga, I. C., Chidester, D. L. 2014. Early social deprivation negatively affects social skill acquisition in chimpanzees (Pan troglodytes). Animal Cognition 17(2), 407–414.

In a highly social species like chimpanzees, the process by which individuals become attuned to their social environment may be of vital importance to their chances of survival. Typically, this socialization process, defined by all...

Chelluri, G. I., Ross, S. R., Wagner, K. E. 2013. Behavioral correlates and welfare implications of informal interactions between caretakers and zoo-housed chimpanzees and gorillas. Applied Animal Behaviour Science 147, 306-315.

In captive animal facilities, human staff members are a relevant part of the animals’ social environment in addition to providing care and managing the social group. Structured, predictable interactions and relaxed, spontaneous contacts may all...

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...

Savage, S. 2013. Kidding around in the laboratory animal facility - Goat enrichment. Enrichment Record 14, 14-15.

Goat enrichment can be incredibly rewarding, not only for the goat, but for personnel as well. In our facility, we often refer to goatenrichment tasks as technician (or vet!) enrichment. Somewhere in the evolutionary development...

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...

Patt, A., Gygax, L., Wechsler, B. et al. 2013. Factors influencing the welfare of goats in small established groups during the separation and reintegration of individuals. Applied Animal Behaviour Science 144(1-2), 63-72.

As a goat's separation from or reintegration into its group is likely to have an adverse effect on the welfare of both the separated goat and the remaining goats in the group, management procedures need...

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...