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. 
André, V., Gau, C., Scheideler, A. et al. 2018. Laboratory mouse housing conditions can be improved using common environmental enrichment without compromising data. PLOS Biology 16(4), e2005019.

Animal welfare requires the adequate housing of animals to ensure health and well-being. The application of environmental enrichment is a way to improve the well-being of laboratory animals. However, it is important to know whether...

Brochu, C. P., Winnicker, C. L., Provencher, A. L. et al. 2018. Effects of nesting material on the toxicologic assessment of cyclophosphamide in Crl:CD1(ICR) mice. JAALAS 57(4), 340-349.

The provision of nesting material benefits mice by reducing cold stress, improving feed conversion, increasing litter size, and improving adaptive immunity. The effects of toxins are sensitive to environmental changes, and the introduction of novel...

Giles, J. M., Whitaker, J. W., Moy, S. S. et al. 2018. Effect of environmental enrichment on aggression in BALB/cJ and BALB/cByJ mice monitored by using an automated system. JAALAS 57(3), 236-243.

Aggression among mice remains a common undesirable problem in laboratory settings, and animal welfare and scientific outcomes may become compromised depending on the severity of aggression. This study evaluated the effect of cage enrichment comprising...

Walker, M., Mason, G. 2018. A comparison of two types of running wheel in terms of mouse preference, health, and welfare. Physiology & Behavior 191, 82-90.

Voluntary wheel running occurs in mice of all strains, sexes, and ages. Mice find voluntary wheel running rewarding, and it leads to numerous health benefits. For this reason wheels are used both to enhance welfare...

Wagman, J. D., Lukas, K. E., Dennis, P. M. et al. 2018. A work-for-food enrichment program increases exploration and decreases stereotypies in four species of bears. Zoo Biology 37(1), 3–15.

Zoo‐housed bears are prone to exhibiting stereotypic behaviors, generally considered indicators of negative welfare. We explored the effects of a variable‐time feeding enrichment schedule on behavioral indicators of welfare in four bear species at Cleveland...

Clarke, D., Ioannou, L. 2018. Introduction of gang caging for group housed rats. Animal Technology and Welfare 17(2), 136-137.

Using an existing gang cage designed for ferrets, we developed a version that would be suitable for housing rats. Caging consisted of 3 floors with a combined floor area of 11620m, connected by 2 ladders...

Dean, L., Swan, J., Lopez-Salesansky, N. et al. 2018. The introduction of a cable tie swing and its impact on animal welfare. Animal Technology and Welfare 17(1), 43-45.

Common enrichment for mice is usually restricted to the floor and easily damaged, leading to frequent replacement. We have been studying the behaviour of NSG mice towards a 'swing' made from plastic cable ties. This...

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...

Sikora, M., Nicolas, C., Istin, M. et al. 2018. Generalization of effects of environmental enrichment on seeking for different classes of drugs of abuse. Behavioural Brain Research 341, 109-113.

Background: Addiction is a chronic disease characterized by persistent vulnerability to relapse during abstinence. In animal models of addiction, accumulating evidence suggests that exposure to environmental enrichment (EE) during periods of abstinence can have curative...

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...

Graham, C., von Keyserlingk, M. A. G., Franks, B. 2018. Free-choice exploration increases affiliative behaviour in zebrafish. Applied Animal Behaviour Science 203, 103-110.

Cognitive stimulation has been shown to be rewarding and capable of eliciting positive emotions in several species. In contrast to the abundant learning and exploration opportunities available in nature, captive environments can be under-stimulating—with the...

Graham, C., von Keyserlingk, M. A. G., Franks, B. 2018. Zebrafish welfare: Natural history, social motivation and behaviour. Applied Animal Behaviour Science 200, 13-22.

Zebrafish are now one of the most used animal model species in scientific research worldwide. Our current knowledge of wild zebrafish is limited to an estimated range of their natural habitats and their tendencies to...

Heimberg, C. K., Jespersen, A., Moe, R. O. 2018. Tail tip lesions in mink (Neovison vison): Effects of an additional hammock in multilevel cages. Animals 8(11), 214.

The occurrence of wounds in different anatomical regions, such as tail tip lesions, is an important welfare concern in farmed mink. This study investigated whether mechanical factors attributed to cage design in multilevel cages may...

Schou, T. M., Palme, R., Malmkvist, J. 2018. Prolonged nest building increase the reproductive outcome in American female mink. Applied Animal Behaviour Science Volume 207, 98-107.

The timing of the onset of maternal-related nest building in American mink is unknown, and it is expected that farmed mink are highly motivated to perform nest building during times with restricted access to nesting...

Sparling, J. E., Baker, S. L., Bielajew, C. 2018. Effects of combined pre- and post-natal enrichment on anxiety-like, social, and cognitive behaviours in juvenile and adult rat offspring. Behavioural Brain Research 353, 40-50.

The pre- and post-natal periods are characterized by unrivalled growth and are sensitive to environmental changes. A correctly stimulating early environment is essential for developing natural behaviors and maintaining affective wellness. Five litters of rat...

Hankenson, F. C., Marx, J. O., Gordon, C. J. et al. 2018. Effects of rodent thermoregulation on animal models in the research environment. Comparative Medicine 68(6), 425–438.

To best promote animal wellbeing and the efficacy of biomedical models, scientific, husbandry, and veterinary professionals must consider the mechanisms, influences, and outcomes of rodent thermoregulation in contemporary research environments. Over the last 2 decades...

Lee, C. J., Tyler, C. R., Paull, G. C. et al. 2018. Can simple tank changes benefit the welfare of laboratory zebrafish Danio rerio? Journal of Fish Biology 92(3), 653-659.

This study examined the effects of simple changes in the tank environment on the wellbeing of laboratory-maintained zebrafish Danio rerio. Groups of D. rerio were either housed in stable environments (where they were maintained in...

Allen, C., Duggan, L., Fox, M. et al. 2018. Attempting enrichment harmonization across multiple sites and embracing our differences. Laboratory Animal Science Professional 5(4) (December), 48-51.

A glabal enrichment committee incorporates active members from each of the company’s 6 sites and works towards harmonization of enrichment practices. One of the hot topics is attempting to standardize mouse enrichment and social housing...

Menke, C., Pisharath, H., Goodchild, L. et al. 2018. The use of enrichment to reduce fighting in male laboratory mice. Laboratory Animal Science Professional 6(1) (March), 44-45.

Typical husbandry solutions for aggressive mice are individual housing or separation into smaller groups. Individual housing is stressful to mice, while separation into smaller groups can increase housing-related costs for the researchers. To alleviate these...

Robison, L. S., Popescu, D. L., Anderson, M. E. et al. 2018. The effects of volume versus intensity of long-term voluntary exercise on physiology and behavior in C57/Bl6 mice. Physiology & Behavior 194, 218-232.

Cardiovascular exercise (CVE) is associated with healthy aging and reduced risk of disease in humans, with similar benefits seen in animals. Most rodent studies, however, have used shorter intervention periods of a few weeks to...

Gjendal, K., Lund Ottesen, J., Bratbo Sørensen, D. 2018. Does colour matter? Preference of mice for different colours of the house mouse igloo: An observational study. Scandinavian Journal of Laboratory Animal Science 44(6).

It is argued that mice have poor colour vision and are insensitive to the colour red, which they in theory perceive as dark. Therefore, the red tinted Bio-Serv Mouse Igloo® is used to provide mice...

Volgin, A. D., Yakovlev, O. V., Demin, K. A. et al. 2018. Understanding the role of environmental enrichment in zebrafish neurobehavioral models. Zebrafish 15(5), 425-432.

Environmental stimuli are critical in preclinical research that utilizes laboratory animals to model human brain disorders. The main goal of environmental enrichment (EE) is to provide laboratory animals with better choice of activity and greater...

Bayne, K. 2018. Environmental enrichment and mouse models: Current perspectives. Animal Models and Experimental Medicine 1(2), 82-90.

The provision of environmental enrichment to numerous species of laboratory animals is generally considered routine husbandry. However, mouse enrichment has proven to be very complex due to the often contradictory outcomes (animal health and welfare...

Gurfein, B. T., Hasdemir, B., Milush, J. M. et al. 2017. Enriched environment and stress exposure influence splenic B lymphocyte composition. PLOS ONE 12(7), e0180771.

Prolonged chronic stress has deleterious effects on immune function and is associated with numerous negative health outcomes. The spleen harbors one-fourth of the body’s lymphocytes and mediates both innate and adaptive immune responses. However, the...

Gjendal, K., Sørensen, D. B., Kiersgaard, M. K. et al. 2017. Hang on: An evaluation of the hemp rope as environmental enrichment in C57BL/6 mice. Animal Welfare 26(4), 437-447.

When introducing environmental enrichment in laboratory animals, positive and/or negative effects on behavioural and physiological parameters should be evaluated. This three-step randomised controlled trial in male C57BL/6 mice investigated the effect of supplementing the environment...