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. 
Toyoshima, M., Yamada, K., Sugita, M. et al. 2018. Social enrichment improves social recognition memory in male rats. Animal Cognition 21(3), 345–351.

The social environment is thought to have a strong impact on cognitive functions. In the present study, we investigated whether social enrichment could affect rats’ memory ability using the “Different Objects Task (DOT),” in which...

Redfern, W. S., Tse, K., Grant, C. et al. 2017. Automated recording of home cage activity and temperature of individual rats housed in social groups: The Rodent Big Brother project. PLOS ONE 12(9), e0181068.

Measuring the activity and temperature of rats is commonly required in biomedical research. Conventional approaches necessitate single housing, which affects their behavior and wellbeing. We have used a subcutaneous radiofrequency identification (RFID) transponder to measure...

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...

DiVincenti, L. Jr., Rehrig, A. 2017. Social behavior of adult male New Zealand White rabbits housed in groups or pairs in the laboratory. Journal of Applied Animal Welfare Science 20(1), 86-94.

Rabbits are usually singly housed in laboratories, but a new emphasis on providing social housing for social species has prompted exploration of alternative housing for this species. However, a paucity of literature on the social...

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...

Walsh, J., Percival, A., Turner, P. 2017. Efficacy of blunt force trauma, a novel mechanical cervical dislocation device, and a non-penetrating captive bolt device for on-farm euthanasia of pre-weaned kits, growers, and adult commercial meat rabbits. Animals 7(12), 100.

The commercial meat rabbit industry is without validated on-farm euthanasia methods, potentially resulting in inadequate euthanasia protocols. We evaluated blunt force trauma (BFT), a mechanical cervical dislocation device (MCD), and a non-penetrating captive bolt device...

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...

Boivin, G. P., Hickman, D. L., Creamer-Hente, M. A. et al. 2017. Review of CO2 as a euthanasia agent for laboratory rats and mice. JAALAS 56(5), 491-499.

Selecting an appropriate, effective euthanasia agent is controversial. Several recent publications provide clarity on the use of CO2 in laboratory rats and mice. This review examines previous studies on CO2 euthanasia and presents the current...

de Souza Dyer, C., Brice, A. K., Marx, J. O. 2017. Intraperitoneal administration of ethanol as a means of euthanasia for neonatal mice (Mus musculus). JAALAS 56(3), 299-306.

The humane euthanasia of animals in research is of paramount importance. Neonatal mice frequently respond differently to euthanasia agents when compared with adults. The AVMA's Guidelines for the Euthanasia of Animals includes intraperitoneal injection of...

Boivin, G. P., Bottomley, M. A., Schiml, P. A. et al. 2017. Physiologic, behavioral, and histologic responses to various euthanasia methods in C57BL/6NTac male mice. JAALAS 56(1), 69-78.

Rodent euthanasia using exposure to increasing concentrations of CO2 has come under scrutiny due to concerns of potential pain during the euthanasia process. Alternatives to CO2, such as isoflurane and barbiturates, have been proposed as...

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...

Marshall, K., Wolford, H., Martin, L. 2017. Creatively meeting the standards – taking rabbit housing to the next level. Animal Technology and Welfare 16(3), 226-228.

The 8th Edition of the Guide for the Care and Use of Laboratory Animals clarified its language regarding housing social species, specifying that, “Single housing of social species should be the exception…”. This is a...

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...

Harvey, B. S., Dudzinski, K. M., Kuczaj, S. A. 2017. Associations and the role of affiliative, agonistic, and socio-sexual behaviors among common bottlenose dolphins (Tursiops truncatus). Behavioural Processes 135, 145-156.

Little is known about the specific behavioral exchanges that occur on a day-to-day basis between dyads of common bottlenose dolphins (Tursiops truncatus). This study assesses the proportion of time dyads spend in proximity (within ∼2...

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...

Clegg, I. L., Rödel, H. G., Delfour, F. 2017. Bottlenose dolphins engaging in more social affiliative behaviour judge ambiguous cues more optimistically. Behavioural Brain Research 322, 115-122.

Cognitive bias tests measure variation in emotional appraisal and are validated methods to assess animals’ affective states. However, the link between social behaviours and cognitive bias has not yet been investigated. Bottlenose dolphins are a...

Zomeño, C., Birolo, M., Zuffellato, A. et al. 2017. Aggressiveness in group-housed rabbit does: Influence of group size and pen characteristics. Applied Animal Behaviour Science 194, 79-85.

The aim of this work was to study how the group size and the number of doorways in a pen may influence the aggressive interactions throughout the reproductive cycle among does kept in a part-time...

Guedes, S. R., Valentim, A. M., Antunes, L. M. 2017. Mice aversion to sevoflurane, isoflurane and carbon dioxide using an approach-avoidance task. Applied Animal Behaviour Science 189, 91-97.

Euthanasia of laboratory animals is one of the main concerns for animal welfare, especially the use of carbon dioxide (CO2) which has been described to induce aversive-like behaviours. In order to refine mass euthanasia in...

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...

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...

Valentim, A. M., Guedes, S. R., Pereira, A. M. et al. 2016. Euthanasia using gaseous agents in laboratory rodents. Laboratory Animals 50(4), 241-253.

Several questions have been raised in recent years about the euthanasia of laboratory rodents. Euthanasia using inhaled agents is considered to be a suitable aesthetic method for use with a large number of animals simultaneously...

Powell, K., Ethun, K., Taylor, D. K. 2016. The effect of light level, CO2 flow rate, and anesthesia on the stress response of mice during CO2 euthanasia. Lab Animal 45(10), 386-395.

Euthanasia protocols are designed to mitigate the stress experienced by animals, and an environment that induces minimal stress helps achieve that goal. A protocol that is efficient and practical in a typical animal research facility...