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. 
Barker, T. H., George, R. P., Howarth, G. S. et al. 2017. Assessment of housing density, space allocation and social hierarchy of laboratory rats on behavioural measures of welfare. PLOS ONE 12(9), e0185135.

Minimum space allowances for laboratory rats are legislated based on weight and stocking rates, with the understanding that increased housing density encourages crowding stress. However, there is little evidence for these recommendations, especially when considering...

Weber, E. M., Dallaire, J. A., Gaskill, B. N. et al. 2017. Aggression in group-housed laboratory mice: Why can’t we solve the problem? Lab Animal 46(4), 157-161.

Group housing is highly important for social animals. However, it can also give rise to aggression, one of the most serious welfare concerns in laboratory mouse husbandry. Severe fighting can lead to pain, injury and...

Gaskill, B. N., Stottler, A. M., Garner, J. P. et al. 2017. The effect of early life experience, environment, and genetic factors on spontaneous home-cage aggression-related wounding in male C57BL/6 mice. Lab Animal 46(4), 176-184.

Aggression is a major welfare issue in mice, particularly when mice unfamiliar to each other are first placed in cages, as happens on receipt from a vendor, and following cage cleaning. Injuries from aggression are...

Kappel, S., Hawkins, P., Mendl, M. 2017. To group or not to group? Good practice for housing male laboratory mice. Animals 7(12), 88.

It is widely recommended to group-house male laboratory mice because they are ‘social animals’, but male mice do not naturally share territories and aggression can be a serious welfare problem. Even without aggression, not all...

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...

Jorgensen, M. J., Lambert, K. R., Breaux, S. D. et al. 2017. Pair housing of vervets/African green monkeys for biomedical research. American Journal of Primatology 79(1), e22501.

Vervets, also known as African green monkeys, are a nonhuman primate species widely used in biomedical research. However, there are currently few references available describing techniques and rates of success for pair‐housing this species. We...

Ross, A. P., Norvelle, A., Choi, D. C. et al. 2017. Social housing and social isolation: Impact on stress indices and energy balance in male and female Syrian hamsters (Mesocricetus auratus). Physiology & Behavior 177, 264-269.

Although Syrian hamsters are thought to be naturally solitary, recent evidence from our laboratory demonstrates that hamsters may actually prefer social contact. Hamsters increase their preference for a location associated with an agonistic encounter regardless...

Holgate, J. Y., Garcia, H., Chatterjee, S. et al. 2017. Social and environmental enrichment has different effects on ethanol and sucrose consumption in mice. Brain and Behavior 7(8), e00767.

Factors leading to the harmful consumption of substances, like alcohol and sucrose, involve a complex interaction of genes and the environment. While we cannot control the genes we inherit, we can modify our environment. Understanding...

Pasquarelli, N., Voehringer, P., Henke, J. et al. 2017. Effect of a change in housing conditions on body weight, behavior and brain neurotransmitters in male C57BL/6J mice. Behavioural Brain Research 333, 35-42.

The development of modern housing regimes such as individually ventilated cage (IVC) systems has become very popular and attractive in order to reduce spreading of pathogenic organisms and to lower the risk to develop a...

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...

Daoudi, S., Badihi, G., Buchanan-Smith, H. 2017. Is mixed-species living cognitively enriching? Enclosure use and welfare in two captive groups of tufted capuchins (Sapajus apella) and squirrel monkeys (Saimiri sciureus). Animal Behavior and Cognition 4(1).

Non-human primates have complex relationships with conspecifics and also other animals with whom they share their habitat in the wild. Some primates, such as capuchin monkeys (Sapajus apella) and squirrel monkeys (Saimiri sciureus), naturally associate...

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...

Kamakura, R., Kovalainen, M., Leppaluoto. J. et al. 2016. The effects of group and single housing and automated animal monitoring on urinary corticosterone levels in male C57Bl/6 mice. Physiological Reports 4(3), e12703.

Mice are used extensively in physiological research. Automated home‐cage systems have been developed to study single‐housed animals. Increased stress by different housing conditions might affect greatly the results when investigating metabolic responses. Urinary corticosteroid concentration...

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...

Karrberg, L., Andersson, L., Kastenmayer, R. J. et al. 2016. Refinement of habituation procedures in diet-induced obese mice. Laboratory Animals 50(5), 397-399.

Orogastric gavage, while a common method for delivering experimental substances in mice, has been shown to induce stress. To minimize the associated stress with this procedure, sham gavage prior to the start of experiment is...

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...

Tokumaru, R. S., Ades, C., Monticelli, P. F. 2015. Social support does not require attachment: Any conspecific tranquilizes isolated guinea-pig pups. Applied Animal Behaviour Science 171, 197-203.

Guinea pig pups produce typical distress whistles when isolated. Whistles’ frequency is decreased or abolished when they contact with the mother and, to a lesser degree, a sibling or even an unfamiliar female, is regained...

Clipperton-Allen, A. E., Ingrao, J. C., Ruggerio, L. et al. 2015. Long-term provision of environmental resources alters behavior but not physiology or neuroanatomy of male and female BALB/c and C57BL/6 mice. JAALAS 54(6), 718-30.

Few studies have evaluated the long-term effects of providing environmental resources to mice. This consideration is important given that mice are often maintained in vivaria for months. We evaluated the effects of providing simple cage...

Spiezio, C., Piva, F., Regaiolli, B. et al. 2015. Positive reinforcement training: a tool for care and management of captive vervet monkeys (Chlorocebus aethiops). Animal Welfare 24, 283-290.

In modern zoos, training should be an integral component of the animal care and management. The benefits of training include the opportunity for positive interactions with caretakers. This study was carried out with a group...

Jirkof, P. 2015. Effects of experimental housing conditions on recovery of laboratory mice. Lab Animal 44(2), 65-70.

The beneficial effects of environment and social support during disease recovery in humans are widely accepted. Because laboratory mice are social animals and are highly motivated to interact with each other and with their environment...

Maher, R. L., Barbash, S. M., Lynch, D. V. et al. 2015. Group housing and nest building only slightly ameliorate the cold stress of typical housing in female C57BL/6J mice. American Journal of Physiology 308(12), R1070-R1079.

Huddling and nest building are two methods of behavioral thermoregulation used by mice under cold stress. In the laboratory, mice are typically housed at an ambient temperature (Ta) of 20°C, well below the lower end...

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...

Baszczak, J. A. 2014. An easy solution for social housing larger guinea pigs in research. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 565 (Abstract #P61).

The standard microisolation caging for guinea pigs, Cavia porcellus, allows for group housing up to a combined weight of 350 g. However, as mandated by the USDA, research facilities must socially house guinea pigs with...

Cikanek, S. J., Nockold, S., Brown, J. L. et al. 2014. Evaluating group housing strategies for the ex-situ conservation of harlequin frogs (Atelopus spp) using behavioral and physiological indicators. PLOS ONE 9(2), e90218.

We have established ex situ assurance colonies of two endangered Panamanian harlequin frogs, Atelopus certus and Atelopus glyphus, but observed that males fought with each other when housed as a group. Housing frogs individually eliminated...

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...