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. 
Reading, P., Reading, R., Branstone, C. 2020. Mirror, mirror, on the wall. Animal Technology and Welfare 19(1), 98-100.

When mice are grouped together for the first time, it is a novel experience filled with new sights and smells that will stress the animal too much and may cause aggression. By adding a mirror...

Hohlbaum, K., Frahm, S., Rex, A. et al. 2020. Social enrichment by separated pair housing of male C57BL/6JRj mice. Scientific Reports 10, 11165.

Laboratory male mice are often housed individually due to aggressive behavior or experimental requirements, though social isolation can cause welfare issues. As a strategy to refine housing of male mice, we introduce the separated pair...

Bailoo, J. D., Voelkl, B., Varholick, J. et al. 2020. Effects of weaning age and housing conditions on phenotypic differences in mice. Scientific Reports 10, 11684.

Poor reproducibility is considered a serious problem in laboratory animal research, with important scientific, economic, and ethical implications. One possible source of conflicting findings in laboratory animal research are environmental differences between animal facilities combined...

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...

Bodden, C., Wewer, M., Kästner, N. et al. 2021. Not all mice are alike: Mixed-strain housing alters social behaviour. Physiology & Behavior 228, 113220.

The use of millions of mice in scientific studies worldwide emphasises the continuing need for a reduction of sample sizes, however, not at the expense of scientific validity. Split-plot designs have been suggested to enhance...

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...

Borland, J. M., Kim, E., Swanson, S. P. et al. 2020. Effect of aggressive experience in female Syrian hamsters on glutamate receptor expression in the nucleus accumbens. Frontiers in Behavioral Neuroscience 14, 583395.

Our social relationships determine our health and well-being. In rodent models, there is now strong support for the rewarding properties of aggressive or assertive behaviors to be critical for the expression and development of adaptive...

Grífols, R., Zamora, C., Ortega-Saez, I. et al. 2020. Postweaning grouping as a strategy to reduce singly housed male mice. Animals 10(11), 2135.

Rearing laboratory mice in groups is important since social isolation after weaning induces brain alterations, which entails behavioral abnormalities in adulthood. Age is an important factor when grouping males of different litters due to inter-male...

Lefebvre, E., Granon, S., Chauveau, F. 2020. Social context increases ultrasonic vocalizations during restraint in adult mice. Animal Cognition 23(2), 351–359.

Adult mice emit many ultrasonic vocalizations (USVs) during social interaction tasks, but only a few studies have yet reported USVs in stressed adult mice. Our aim was to study which experimental conditions favor USV emission...

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...

Melotti, L., Kästner, N., Eick, A. K. et al. 2019. Can live with ‘em, can live without ‘em: Pair housed male C57BL/6J mice show low aggression and increasing sociopositive interactions with age, but can adapt to single housing if separated. Applied Animal Behaviour Science 214, 79-88.

The basic question as to whether male laboratory mice should be singly or group housed represents a major animal welfare concern within current laboratory animal legislation and husbandry. To better understand the behavioural and physiological...

Nip, E., Adcock, A., Nazal, B. et al. 2019. Why are enriched mice nice? Investigating how environmental enrichment reduces agonism in female C57BL/6, DBA/2, and BALB/c mice. Applied Animal Behaviour Science 217, 73-82.

Compared to female mice raised in large, environmentally enriched (EE) cages, those from “shoebox” non-enriched (NE) cages demonstrate more stereotypic behaviour (SB) and depressive-like effects (i.e. learned helplessness; and inactive-but-awake behaviour [IBA], where a mouse...

Brajon, S., Morello, G. M., Teixeira, M. S. et al. 2019. Social environment as a cause of litter loss in laboratory mouse: A behavioural study. Applied Animal Behaviour Science 218, 104827.

Perinatal mortality is a widespread problem in laboratory mouse breeding and is often manifested by the loss of the entire litter within the first days of life. High mortality is an animal health and welfare...

Liang, F., Yang, S., Zhang, Y. et al. 2019. Social housing promotes cognitive function through enhancing synaptic plasticity in APP/PS1 mice. Behavioural Brain Research 368, 111910.

Previous studies have shown that loneliness increases the risk of AD (Alzheimer’s disease) onset, while active and frequent social housing delays the onset of cognitive impairment. The mechanism of how this occurs remains unclear. In...

Azkona, G., Caballero, J. M. 2019. Implementing strategies to reduce singly housed male mice. Laboratory Animals 53(5), 508–510.

There are different husbandry situations that lead to social isolation of male mice. Besides legal considerations, single housing has a negative impact on behavioural and molecular studies. We have implemented two strategies, the ‘companion mouse’...

Eichner, M., Garcia, K. 2019. Increase in morbidity and mortality in a shipment of red-eared slider turtles (Trachemys scripta elegans). Laboratory Animals 53(6), 634–640.

A cohort of captive-bred red-eared slider turtles, Trachemys scripta, was received from a commercial vendor. Shortly after arrival, several turtles presented as lethargic with subjectively pale skin and multifocal areas of cotton-like tufts in the...

Sherrill, C., Kavanagh, K. 2019. Fight Club: Using housing conditions to curb male cage aggression. Laboratory Animal Science Professional 7(1) (March), 38-40.

Those who have worked with C57BL/6 males know how aggressive they can be towards their cage mates. We poured over academic journals, reading every article we could find regarding male home cage aggression. Three articles...

Lidster, K., Owen, K., Browne, W. J. et al. 2019. Cage aggression in group-housed laboratory male mice: An international data crowdsourcing project. Scientific Reports 9, 15211.

Aggression in group-housed laboratory mice is a serious animal welfare concern. Further understanding of the causes of mouse aggression could have a significant impact on a large number of laboratory animals. The NC3Rs led a...

Zidar, J., Weber, E. M., Ewaldsson, B. et al. 2019. Group and single housing of male mice: Collected experiences from research facilities in Sweden. Animals 9(12), 1010.

The mouse is the most commonly used mammal in scientific research, and housed in research facilities around the world. Mice are a social species, but when housing male mice together in a confined environment in...

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...

Coke, C., Skoumbourdis, E., Rodgers, J. C. et al. 2018. Blunting/cutting canines of adult male monkeys: A discussion by the Laboratory Animal Refinement & Enrichment Forum. Animal Technology & Welfare 17(2), 105-107.

"When you keep adult Rhesus macaque (Macaca mulatta) males, adult Cynomolgus (Macaca fascicularis) males or adult Vervet males (Chlorocebus pygerythrus), in the same enclosure, is it advisable to have the canines of the males blunted...

Arakawa, H. 2018. Ethological approach to social isolation effects in behavioral studies of laboratory rodents. Behavioural Brain Research 341, 98-108.

The aim of the present review is to discuss how housing conditions affect behavioral performance in laboratory rodents from an ethological view. Commonly used laboratory rodents such as rats and mice, are originally captured animals...

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...