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. 
Travain, T., Valsecchi, P. 2021. Infrared thermography in the study of animals’ emotional responses: A critical review. Animals 11(9), 2510.

Whether animals have emotions was historically a long-lasting question but, today, nobody disputes that they do. However, how to assess them and how to guarantee animals their welfare have become important research topics in the...

MacLellan, A., Fureix, C., Polanco, A. et al. 2021. Can animals develop depression? An overview and assessment of “depression-like” states. Behaviour 158(14/15), 1303–1353.

Describing certain animal behaviours as 'depression-like' or 'depressive' has become common across several fields of research. These typically involve unusually low activity or unresponsiveness and/or reduced interest in pleasure (anhedonia). While the term 'depression-like' carefully...

Garcia, T., Brown, C., Margolies, D. et al. 2021. Grinding on a last nerve: Attempting to curb food grinding in mice. Laboratory Animal Science Professional 9(6) (November/December), 34-36.

Food grinding, or chewing food without ingestion, is a topic of interest in the laboratory animal community. In addition to increased effort needed to deal with this excess waste and provide suitable microenvironment for animals...

Verjat, A., Devienne, P., Rödel, H. G. et al. 2021. More exploratory house mice judge an ambiguous situation more negatively. Animal Cognition 24(1), 53–64.

Exploration tendency, one of the most investigated animal personality traits, may be driven by either positive (when seeking interesting information) or negative (to reduce the uncertainty of the environment) affective/emotional profiles. To disentangle the valence...

Schneeberger, K., Röder, G., Taborsky, M. 2020. The smell of hunger: Norway rats provision social partners based on odour cues of need. PLOS Biology 18(3), e3000628.

When individuals exchange helpful acts reciprocally, increasing the benefit of the receiver can enhance its propensity to return a favour, as pay-offs are typically correlated in iterated interactions. Therefore, reciprocally cooperating animals should consider the...

Han, Y., Sichterman, B., Maria, C. et al. 2020. Similar levels of emotional contagion in male and female rats. Scientific Reports 10(1), 2763.

Emotional contagion, the ability to feel what other individuals feel without necessarily understanding the feeling or knowing its source, is thought to be an important element of social life. In humans, emotional contagion has been...

Oralman, T. 2020. Confronting crunching: A refinement for the care of mice with the desire to crunch. Animal Technology and Welfare 19(1), 89-91.

‘Crunching’ is the term often used to describe the abnormal behaviour of mice that habitually crunch their pelleted diet, causing substrate levels to rise as the crumbs settle on the cage floor ultimately burying the...

Łapiński, S., Orel, J., Niedbała, P. et al. 2020. Infrared thermography as an indicator of heat loss in fur-chewing chinchillas (Chinchilla lanigera). Journal of Applied Animal Welfare Science 23(3), 338-347.

Fur-chewing is a common problem in chinchilla (Chinchilla lanigera). It may affect the welfare of animals due to heat loss, thereby possibly impacting food and water intake to maintain body temperature. In this context, infrared...

Améndola, L., Weary, D. M. 2020. Understanding rat emotional responses to CO2. Translational Psychiatry 10, 253.

The aim of this review is to summarize evidence regarding rat emotional experiences during carbon dioxide (CO2) exposure. The studies reviewed show that CO2 exposure is aversive to rats, and that rats respond to CO2...

Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...

Munari, C., Ponzio, P., Macchi, E. et al. 2020. A multifactorial evaluation of different reproductive rhythms and housing systems for improving welfare in rabbit does. Applied Animal Behaviour Science 230, 105047.

The most widespread reproductive rhythm practiced in rabbit farming is based on artificial insemination (AI) performed at around 11 days pospartum. This approach results in high production rates, but requires high yearly replacement of animals...

Theil, J. H., Ahloy-Dallaire, J., Weber, E. M. et al. 2020. The epidemiology of fighting in group-housed laboratory mice. Scientific Reports 10(1), 16649.

Injurious home-cage aggression (fighting) in mice affects both animal welfare and scientific validity. It is arguably the most common potentially preventable morbidity in mouse facilities. Existing literature on mouse aggression almost exclusively examines territorial aggression...

McMahon, S. A., Wigham, E. 2020. ‘All Ears’: A questionnaire of 1516 owner perceptions of the mental abilities of pet rabbits, subsequent resource provision, and the effect on welfare. Animals 10(10), 1730.

Pet rabbit welfare is a hidden crisis: Inappropriately housed, fed, and not routinely provided healthcare—rabbits can often suffer painful conditions and shortened lifespans. This study provides novel understanding of owners’ perceptions of rabbits’ mental capabilities...

Dewaele, A., Badonnel, K., Persuy, M.-A. et al. 2020. Effect of environmental exposure to a maternally-learned odorant on anxiety-like behaviors at weaning in mice. Animal Cognition 23(5), 881–891.

Early sensory experience, such as exposure to maternal or other environmental factors, is considered to influence neurocognitive development and behaviors. In many species, exposure to odorants during pregnancy or lactation impacts the morpho-functional development of...

Silber, S., Joshi, S., Pillay, N. 2019. Behavioural syndromes in stereotypic striped mice. Applied Animal Behaviour Science 212, 74-81.

Stereotypical behaviours (SBs) are abnormal, repetitive behaviours often observed in captivity. SBs are linked to impoverished captive conditions, and stereotypic individuals show a particular set of behaviours (e.g. bolder personality, greater activity) indicating proactive coping...

LaFollette, M. R., Swan, M. P., Smith, R. K. et al. 2019. The effects of cage color and light intensity on rat affect during heterospecific play. Applied Animal Behaviour Science 219, 104834.

Environmental enrichment provides physiological and emotional benefits to laboratory rodents. Red tinted shelters are a common enrichment found in laboratories that provide rodents with a hiding space shielded from bright light. Red tinting alters the...

Brudzynski, S. M. 2019. Emission of 22 kHz vocalizations in rats as an evolutionary equivalent of human crying: Relationship to depression. Behavioural Brain Research 363, 1-12.

There is no clear relationship between crying and depression based on human neuropsychiatric observations. This situation originates from lack of suitable animal models of human crying. In the present article, an attempt will be made...

Jirkof, P., Rudeck, J., Lewejohann, L. 2019. Assessing affective state in laboratory rodents to promote animal welfare—What is the progress in applied refinement research? Animals 9(12), 1026.

In the past, there was a strong focus on avoiding or reducing negative animal welfare in animal experimentation. Recently, the importance of promoting positive animal welfare in laboratory animals has been highlighted. To ensure and...

McMillan, F. D. (ed). 2019. Mental Health and Well-being in Animals (2nd ed). CABI, Wallingford, UK.

This second edition is fully revised, expanded, and comprehensively updated with the most current knowledge about the full array of mental health issues seen in animals. Written by key opinion leaders, internationally-recognized experts and specialists...

Costa, R., Sousa, C., Llorente, M. 2018. Assessment of environmental enrichment for different primate species under low budget: A case study. Journal of Applied Animal Welfare Science 21(2), 185-199.

The 2011 European Union Zoo Inquiry presented evidence that most zoos fail to achieve adequate levels of nonhuman animal welfare. Appropriate environmental enrichment (EE) can play a role in the promotion of welfare. However, financial...

Aujnaraina, A. B., Luoa, O. D., Taylor, N. et al. 2018. Effects of exercise and enrichment on behaviour in CD-1 mice. Behavioural Brain Research 342, 43-50.

A host of scholarly work has characterized the positive effects of exercise and environmental enrichment on behaviour and cognition in animal studies. The purpose of this study was to investigate the uptake and longitudinal impact...

Wang, R., Hausknechta, K. A., Haj-Dahmane, S. et al. 2018. Decreased environmental complexity during development impairs habituation of reinforcer effectiveness of sensory stimuli. Behavioural Brain Research 337, 53-60.

Previous research has shown that rats reared in simple/impoverished environments demonstrate greater repetitive responding for sensory reinforcers (e.g., light onset). Moreover, the brains of these rats are abnormally developed, compared to brains of rats reared...

Lutz, C. K. 2018. A cross-species comparison of abnormal behavior in three species of singly-housed old world monkeys. Applied Animal Behaviour Science 199, 52-58.

Abnormal behavior occurs in a number of captive nonhuman primate species and is often used as an indicator of welfare. However, reported levels of abnormal behavior often vary across species, making general welfare judgments difficult...

Bailoo, J. D., Murphy, E., Varholick, J. A. et al. 2018. Evaluation of the effects of space allowance on measures of animal welfare in laboratory mice. Scientific Reports 8, 713.

We studied how space allowance affects measures of animal welfare in mice by systematically varying group size and cage type across three levels each in both males and females of two strains of mice (C57BL/6ByJ...

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...