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. 
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...

Williams, L. E., Coke, C. S., Weed, J. L. 2017. Socialization of adult owl monkeys (Aotus sp.) in captivity. American Journal of Primatology 79(1), e22521.

Social housing has often been recommended as one‐way to address the psychological well‐being of captive non‐human primates. Published reports have examined methods to socialize compatible animals by forming pairs or groups. Successful socialization rates vary...

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...

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...

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...

Lopes, V. M., Sampaio, E., Roumbedakis, K. et al. 2017. Cephalopod biology and care, a COST FA1301 (CephsInAction) training school: Anaesthesia and scientific procedures. Invertebrate Neuroscience 17, 8.

Cephalopods are the sole invertebrates included in the list of regulated species following the Directive 2010/63/EU. According to the Directive, achieving competence through adequate training is a requisite for people having a role in the...

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...

Bermejo-Poza, R., De la Fuente, J., Pérez, C. 2016. Reducing the effect of pre-slaughter fasting on the stress response of rainbow trout (Oncorhynchus mykiss). Animal Welfare 25(3), 339-346.

Fasting is commonly used in aquaculture to empty the gut before slaughter, but little is known about how feeding frequency before fasting affects the stress response of trout. To find out more, 240 rainbow trout...

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...

Hawkins, P., Prescott, M., Carbone, L. et al. 2016. A good death? Report of the second Newcastle meeting on laboratory animal euthanasia. Animals 6(9), 50.

Millions of laboratory animals are killed each year worldwide. There is an ethical, and in many countries also a legal, imperative to ensure those deaths cause minimal suffering. However, there is a lack of consensus...

Hickman, D., Fitz, S., Bernabe, C. et al. 2016. Evaluation of low versus high volume per minute displacement CO2 methods of euthanasia in the induction and duration of panic-associated behavior and physiology. Animals 6(8), 45.

Current recommendations for the use of CO 2 as a euthanasia agent for rats require the use of gradual fill protocols (such as 10% to 30% volume displacement per minute) in order to render the...

Enser, S. 2016. Comparison of housing and welfare of group housed rabbits. Animal Technology and Welfare 15(1), 77-79.

This poster is based on welfare improvements gained from group housing rabbits in floor pens in the new Antibody Production Facility with a focus on development, behaviours and environmental enrichment in both male and female...

Buijs, S., Vangeyte, J., Tuyttens, F. A. M. 2016. Effects of communal rearing and group size on breeding rabbits’ post-grouping behaviour and its relation to ano-genital distance. Applied Animal Behaviour Science, 182, 53-60.

Group housing is becoming the standard for many farm animal species, as it is seen as a more welfare friendly way of keeping gregarious animals. Aggression between female breeding rabbits currently obstructs the implementation of...

Bozicovich, T. F. M., Moura, A. S. A. M. T., Fernandes, S. et al. 2016. Effect of environmental enrichment and composition of the social group on the behavior, welfare, and relative brain weight of growing rabbits. Applied Animal Behaviour Science 182, 72-79.

The objective of the study was to investigate if environmental enrichment and the composition of the social group would affect the behavior and relative brain weight of growing rabbits. Rabbits (72 males and 72 females)...

Greenway, E., Jones, K. S., Cooke, G. M. 2016. Environmental enrichment in captive juvenile thornback rays, Raja clavata (Linnaeus 1758). Applied Animal Behaviour Science 182, 86-93.

There are few studies investigating captive conditions for commonly kept public aquaria species. Here the thornback ray (Raja clavata) was used to determine preferred captive conditions via choice tests and behavioural observations. Substrate type, substrate...