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. 
Lambert, H., Cornish, A., Waley, D. 2024. The value of regulating stocking densities in aquaculture must not be dismissed: A reply to Saraiva et al. 2022. Frontiers in Veterinary Science 10.

We would like to rebut the argument made by Saraiva et al. (1) in their paper “Finding the “golden stocking density”: a balance between fish welfare and farmers' perspectives,” that stocking densities should not be...

Eraslan, E., Castelhano-Carlos, M. J., Amorim, L. et al. 2023. Home-cage behavior is impacted by stress exposure in rats. Frontiers in Behavioral Neuroscience 17, 1195011.

Being social animals, rats exhibit a range of social behaviors that help them build social bonds and maintain group cohesion. Behavior is influenced by multiple factors, including stress exposure, and the expression of the impact...

Marquardt, A. E., VanRyzin, J. W., Fuquen, R. W. et al. 2023. Social play experience in juvenile rats is indispensable for appropriate socio-sexual behavior in adulthood in males but not females. Frontiers in Behavioral Neuroscience 16, 1076765.

Social play is a dynamic and rewarding behavior abundantly expressed by most mammals during the juvenile period. While its exact function is debated, various rodent studies on the effects of juvenile social isolation suggest that...

Parsons, M., Stryjek, R., Fendt, M. et al. 2023. Making a case for the free exploratory paradigm: Animal welfare-friendly assays that enhance heterozygosity and ecological validity. Frontiers in Behavioral Neuroscience 17, 1228478.

Animal welfare considerations are an essential part of scientific research. If animals may suffer, then even 26 the most promising research plans can be delayed or rejected and the resulting data may be questionable. 27...

Sen Sarma, O., Frymus, N., Axling, F. et al. 2023. Optimizing zebrafish rearing−Effects of fish density and environmental enrichment. Frontiers in Behavioral Neuroscience 17, 1204021.

Despite its popularity in research, there is very little scientifically validated knowledge about the best practices on zebrafish (Danio rerio) husbandry, which has led to several facilities having their own husbandry protocols. This study was...

Veness, A., Coyle, C., Murphy, S. et al. 2023. Minimising aggression in CD-1 and CD-1 background male mice with different enrichment types. Animal Technology and Welfare 22(1), 74–76.

Cage-mate aggression is a well-known problem that is more prevalent in certain strains of mice and is one of the most common reasons for single housing, increased stress levels, premature death and euthanasia. Numerous methods...

Watanabe, S. 2023. Infrared thermography for non-invasive measurement of social inequality aversion in rodents and potential usefulness for future animal-friendly studies. Frontiers in Behavioral Neuroscience 17, 1131427.

Infrared thermography is a method that detects thermal radiation energy and can measure the body surface temperature of animals from a distance. While rectal temperature has traditionally been used to measure animals’ core temperature, thermal...

Buenhombre, J., Daza-Cardona, E. A., Sousa, P. et al. 2023. Structural environmental enrichment and the way it is offered influence cognitive judgement bias and anxiety-like behaviours in zebrafish. Animal Cognition 26, 563–577.

Environmental enrichment in zebrafish generally reduces anxiety-related behaviours, improves learning in maze trials and increases health and biological fitness. However, certain types of enrichment or certain conditions induce the opposite effects. Therefore, it is essential...

Lupfer, G., Brandenburger, A., Machado, M. et al. 2023. Ultrasonic vocalizations near 30 kHz may indicate excitement rather than distress in female Wistar rats. Applied Animal Behaviour Science 261, 105881.

Rats emit ultrasonic vocalizations (USVs), sometimes referred to as 50-kHz vocalizations, during activities such as play and lower-frequency USVs, sometimes referred to as 22-kHz vocalizations, when experiencing distress. Definitions of 22-kHz vocalizations vary in terms...

Alef, R., Blaser, R. E. 2023. Social group during housing and testing modulates the effect of ethanol on zebrafish (Danio rerio) behavior. Behavioural Processes 209, 104877.

Zebrafish (Danio rerio) are a popular model organism in behavioral pharmacology research due to many genetic and neurological similarities with humans. As a social species, the presence (or absence) of conspecifics during housing and testing...

Fontana, B. D., Alnassar, N., Parker, M. O. 2023. Transgenerational effects of early-life stress on anxiety behavior in zebrafish (Danio rerio). Behavioural Processes 208, 104874.

Early-life adversity impacts on anxiety-related behaviors in adulthood. The effects of such adversity not only affect the animal itself, but can be passed on transgenerationally. Pervasive effects of experimentally-induced early-life stress (ELS) have been documented...

Moëne, O. L., Larsson, M. 2023. A new tool for quantifying mouse facial expressions. ENeuro 10(2) ENEURO.0349-22.2022.

Facial expressions are an increasingly used tool to assess emotional experience and affective state during experimental procedures in animal models. Previous studies have successfully related specific facial features with different positive and negative valence situations...

Bogdan, R., Kayumova, R., Schwarting, R. K. W. et al. 2023. Wildtype peers rescue social play and 50-kHz ultrasonic vocalization deficits in juvenile female Cacna1c heterozygous rats. Frontiers in Behavioral Neuroscience 17.

Healthy brain development depends on early social practices and experiences. The risk gene CACNA1C is implicated in numerous neuropsychiatric disorders, in which key characteristics include deficits in social functioning and communication. Recently, we reported sex-dependent...

Cavieres, G., Bozinovic, F., Bogdanovich, J. M. et al. 2023. Impact of prolonged chronic social isolation stress on behavior and multifractal complexity of metabolic rate in Octodon degus. Frontiers in Behavioral Neuroscience 17.

Social interaction can improve animal performance through the prevention of stress-related events, the provision of security, and the enhancement of reproductive output and survival. We investigated the effects of prolonged chronic social isolation stress on...

Stevens, C., Hammonds, T., Hinchcliffe, J. et al. 2023. Report of the 2022 RSPCA/UFAW Rodent Welfare Group Meeting. Animal Technology and Welfare 22(2), 91–100.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 29 years, so that its members can discuss current welfare research, exchange views on welfare issues and share experiences of...

Tanaka, Y., Nakata, T., Hibino, H. et al. 2023. Classification of multiple emotional states from facial expressions in head-fixed mice using a deep learning-based image analysis. PLOS ONE 18(7), e0288930.

Facial expressions are widely recognized as universal indicators of underlying internal states in most species of animals, thereby presenting as a non-invasive measure for assessing physical and mental conditions. Despite the advancement of artificial intelligence-assisted...

Wiese, T. R., Rey Planellas, S., Betancor, M. et al. 2023. Qualitative Behavioural Assessment as a welfare indicator for farmed Atlantic salmon (Salmo salar) in response to a stressful challenge. Frontiers in Veterinary Science 10.

Animal welfare assessments have struggled to investigate the emotional states of animals while focusing solely on available empirical evidence. Qualitative Behavioural Assessment (QBA) may provide insights into an animal’s subjective experiences without compromising scientific rigor...

Xue, B., Ma, Y.-Y., Zhu, J.-Y. et al. 2023. Chronic social comparison elicits depression- and anxiety-like behaviors and alterations in brain-derived neurotrophic factor expression in male rats. Animal Cognition 26(5), 1505–1519.

Social comparison is a fundamental human characteristic; however, long-term social comparison may induce psychological stress and can lead to depression and anxiety. Recent studies have shown that nonhuman primates compare themselves with others; however, no...

Butcher, G., Davidson, A., Sloanc, A. et al. 2021. An apparatus for automatically training and collecting individualized behavioral data with socially housed rodents. Journal of Neuroscience Methods 365, 109387.

Background: Conventional methods for individually housing, training, and testing rodents in behavioral assays can impose constraints that may limit some kinds of experimental external validity, preempt environmental enrichment, impose heavy experimenter time burdens that limit...

Stryjek, R., Modlinska, K. 2022. Pre-exposure via wire-mesh partition reduces intraspecific aggression in male, wild-type Norway rats. Animal Welfare 31(2), 175-186.

There are instances when animals are introduced and expected to live alongside unfamiliar conspecifics within zoos, laboratories and wildlife sanctuaries. These pairings of unfamiliar animals may result in stress, trauma, or even death, in addition...

Kitchenham, L., Nazal, B., Adcock, A. et al. 2022. Why does lifelong conventional housing reduce the sociability of female mice? Applied Animal Behaviour Science 246, 105532.

Compared to peers raised in well-resourced, 'enriched' environments (‘EE’), female laboratory mice from conventional barren cages are more aggressive to their cage-mates, and less sociable with familiar non-cage-mates (especially if these too are from conventional...

Denommé, M. R., Mason, G. J. 2022. Social buffering as a tool for improving rodent welfare. JAALAS 61(1), 5-14.

The presence of a conspecific can be calming to some species of animal during stress, a phenomenon known as social buffering. For rodents, social buffering can reduce the perception of and reaction to aversive experiences...

Aldhshan, M. S., Mizuno, T. M. 2022. Effect of environmental enrichment on aggression and the expression of brain-derived neurotrophic factor transcript variants in group-housed male mice. Behavioural Brain Research 433, 113986.

Social and environmental factors influence behavior via modulation of brain physiological functions. Environmental enrichment (EE) is an animal housing technique that provides complex sensory, motor, and social stimulation, leading to modifications in the innate aggressiveness...

Fehrenbach, L. A., Adekanye, A. A., Palillo, M. B. et al. 2022. Internal temperatures of packaging for overnight cross-country shipping of zebrafish (Danio rerio). Comparative Medicine 72(3), 195-203.

As the use of zebrafish (Danio rerio) as a research model continues to rise, so too will the shipping and sharing of zebrafish strains across collaborating institutions. If done incorrectly, shipping can result in significant...

Scariot, P. P., Gobatto, C. A., Polisel, E. E. et al. 2022. Early-life mice housed in standard stocking density reduce the spontaneous physical activity and increase visceral fat deposition before reaching adulthood. Laboratory Animals 56(4), 344-355.

Laboratory rodents spend the entire day housed in standard cages that provide a restricted area for movements and might, therefore, limit physical activity. However, it has not been tested in immature rodents of ages ranging...