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. 
Kersemans, V., Wallington, S., Allen, P. D. et al. 2020. Manganese-free chow, a refined non-invasive solution to reduce gastrointestinal signal for T1-weighted magnetic resonance imaging of the mouse abdomen. Laboratory Animals 54(4), 353–364.

Commercial mouse chow is designed to provide a complete, nutrient-rich diet, and it can contain upwards of 100 mg/kg manganese, an essential mineral. Manganese acts as a relaxation time-shortening contrast agent for both T1 and T2...

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...

Larson, M. A. 2020. Alternatives to shipping live mice. Laboratory Animal Science Professional 8(5) (September/October), 52-54.

Many in the lab animal field are familiar with shipping animals from vendor to investigator, from investigator to vendor, and from investigator to investigator. Sharing mouse models represents being good stewards of our animal resources...

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...

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...

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...

Neff, E. P. 2018. Home sweet home cage. Lab Animal 47(10), 261–264.

This feature describes creative ways in which technology can be used to study animals within their home cages, eliminating the need to handle, restrain, and separate them from cage mates. One example includes voluntary brain...

Polissidis, A., Zelelak, S., Nikita, M. et al. 2017. Assessing the exploratory and anxiety-related behaviors of mice. Do different caging systems affect the outcome of behavioral tests? Physiology & Behavior 177, 68-73.

Ample studies have shown that housing can affect the health, welfare and behavior of mice and therefore, the outcomes of certain experiments. The aim of this study was to investigate if three widely used housing...

Barker, T. H., Bobrovskaya, L., Howarth, G. S. et al. 2017. Female rats display fewer optimistic responses in a judgment bias test in the absence of a physiological stress response. Physiology & Behavior 173, 124-131.

Metabolic cages are a type of housing used in biomedical research. Metabolic cage housing has been demonstrated to elicit behavioural and physiological changes in rodents housed within them. The nature of this effect has been...

Simpson, D. 2017. Investigation of transportation on rat acclimatisation using novel cage side recording equipment (Rodent Big Brother). Animal Technology and Welfare 16(1), 1-12.

The transportation of animals from supplier to experimental facility is one of the biggest stressors to animals in research. Transportation unavoidably causes stress and when the animals arrive at the testing facility they require a...

Kleefeld, S., Bannerton, K., Kelly, J.2017. Effect of moderate environmental enrichment on commonly used behavioural tests in rats. Animal Technology and Welfare 16(1), 75-76.

The environment that laboratory animals are housed in should reflect their natural habitats in a manner that can satisfy their innate physiological and behavioural needs. This includes nest building, hiding, exploring and foraging. Providing environmental...

Tucker, R. D. 2017. Woodchuck College. Laboratory Animal Science Professional 5(2) (June), 33-36.

Marmota monax is a valuable laboratory animal species used in studies of Hepatitis B virus (HBV), food intake, obesity, hibernation, and circannual cycles. This article describes the woodchuck’s (also known as groundhog) natural behavior and...

Makowska, I. J., Weary, D. M. 2016. Differences in anticipatory behaviour between rats (Rattus norvegicus) housed in standard versus semi-naturalistic laboratory environments. PLOS ONE 11(1), e0147595.

Laboratory rats are usually kept in relatively small cages, but research has shown that they prefer larger and more complex environments. The physiological, neurological and health effects of standard laboratory housing are well established, but...

Heyse, N. C., Brenes, J. C., Schwarting, R. K. W. 2015. Exercise reward induces appetitive 50-kHz calls in rats. Physiology & Behavior 147, 131-140.

Rats express affective states by visible behaviors (like approach or flight) and through different kinds of ultrasonic vocalizations (USV). 50-kHz calls are thought to reflect positive affective states since they occur during rewarding situations like...

Bethell, E. J., Koyama, N. F. 2015. Happy hamsters? Enrichment induces positive judgement bias for mildly (but not truly) ambiguous cues to reward and punishment in Mesocricetus auratus. Royal Society Open Science 2, 140399.

Recent developments in the study of animal cognition and emotion have resulted in the ‘judgement bias’ model of animal welfare. Judgement biases describe the way in which changes in affective state are characterized by changes...

Bode, A. E., Barber, H. 2014. Use of vinyl nonadhesive tape as an alternative for positioning rodents in small animal imaging. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 597-598. (Abstract #P185).

Specific positioning for different imaging modalities is essential in our small animal imaging core. While we have different animal holders designed to position the animal inside the MRI, additional securing of the animal to the...

Bartal, I. B.-A., Rodgers, D. A., Sarria, M. S. et al. 2014. Pro-social behavior in rats is modulated by social experience. eLife 3, e01385.

In mammals, helping is preferentially provided to members of one’s own group. Yet, it remains unclear how social experience shapes pro-social motivation. We found that rats helped trapped strangers by releasing them from a restrainer...

Jones, C. E., Riha, P. D., Gore, A. C. et al. 2014. Social transmission of Pavlovian fear: Fear-conditioning by-proxy in related female rats. Animal Cognition 17(3), 827–834.

Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a foot-shock) leads to associative learning such that the tone alone will elicit a conditioned response (e.g., freezing)...

Makowska, I. J., Weary, D. M. 2013. Assessing the emotions of laboratory rats. Applied Animal Behaviour Science 148, 1-12.

Rats are one of the most commonly used species in research, and decades of testing have yielded a large amount of information pertaining to their experience of emotion. The aim of this review is to...

Walters, S. L., Torres-Urbano, C. J., Chichester, L. et al. 2012. The impact of huts on physiological stress: A refinement in post-transport housing of male guinea pigs (Cavia porcellus). Laboratory Animals 46(3), 220-224.

The ideal animal model would contribute no confounding variables in experimental science. Variables affect experimental design resulting in increased animal use or repeated studies. We demonstrated a simple refinement which may reduce the number of...

Gewin, V. 2011. Rats free each other from cages. Nature News.

Following a two-week introduction period, pairs of rats were put inside an arena. One was trapped inside a central restrainer, while the other roamed free in the larger space. By day six or seven, on...