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...

Dudley, E. S., Boivin, G. P. 2018. Evaluation of a commercially available euthanasia solution as a voluntarily ingested euthanasia agent in laboratory mice. JAALAS 57(1), 30-34.

All currently accepted methods of euthanasia for laboratory mice involve some degree of stress, fear, anxiety, or pain. We evaluated the voluntary oral administration of a euthanasia drug in 99 male and 81 female mice...

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...

Lahger, C., Laska, M. 2018. Behavioral responses of CD-1 mice to conspecific and heterospecific blood odors and to a blood odor component. Physiology & Behavior 184, 2015-210.

The odor of blood may have both aversive and attractive properties for mammals, depending on the species of the odor donor and the species perceiving the odor. To better understand the informational content of blood...

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...

Creamer-Hente, M. A., Lao, F. K., Dragos, Z. P. et al. 2018. Sex- and strain-related differences in the stress response of mice to CO₂ euthanasia. JAALAS 57(5), 513–519.

The 2013 edition of the AVMA Guidelines for the Euthanasia of Animals recommends a 10% to 30% volume displacement rate (VDR) per minute for CO2 euthanasia of rodents. Here we sought to evaluate behavior and...

Perdue, B. M., Beran, M. J., Washburn, D. A. 2018. A computerized testing system for primates: Cognition, welfare, and the Rumbaughx. Behavioural Processes 156, 37-50.

Innovations in apparatus technology come about for a variety of reasons such as the need to use the same methodology with various species, the opportunity to present dynamic and carefully controlled stimuli, the goal of...

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...

Heyworth, C., Olivo, D. 2018. Environmental and psychological enrichment for NHPs reimagined and repurposed. Laboratory Animal Science Professional 5(4) (December), 39-43.

This article describes creative enrichment ideas for nonhuman primates, including celery stalks embedded with seeds; paper rolled into tubes, braided and filled with fruit and seeds; pineapple crowns loaded with treats; dry spaghetti noodles coated...

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...

Marquardt, N., Feja, M., Hünigen, H. et al. 2018. Euthanasia of laboratory mice: Are isoflurane and sevoflurane real alternatives to carbon dioxide? PLOS ONE 13(9), e0203793.

In the European Union (EU) millions of laboratory mice are used and killed for experimental and other scientific purposes each year. Although controversially discussed, the use of carbon dioxide (CO2) is still permitted for killing...

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...

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...

Robinson-Junker, A., Morin, A., Pritchett-Corning, K. et al. 2017. Sorting it out: Bedding particle size and nesting material processing method affect nest complexity. Laboratory Animals 51(2), 170-180.

As part of routine husbandry, an increasing number of laboratory mice receive nesting material in addition to standard bedding material in their cages. Nesting material improves health outcomes and physiological performance in mice that receive...

Boivin, G. P., Hickman, D. L., Creamer-Hente, M. A. et al. 2017. Review of CO2 as a euthanasia agent for laboratory rats and mice. JAALAS 56(5), 491-499.

Selecting an appropriate, effective euthanasia agent is controversial. Several recent publications provide clarity on the use of CO2 in laboratory rats and mice. This review examines previous studies on CO2 euthanasia and presents the current...

Johnson, J. S., Taylor, D. J., Green, A. R. et al. 2017. Effects of nesting material on energy homeostasis in BALB/cAnNCrl, C57BL/6NCrl, and Crl:CD1(ICR) mice housed at 20 °C. JAALAS 56(3), 254-259.

Discrepancies exist between the preferred temperature range for mice (26 to 32 °C) and current recommendations (20 to 26 °C), which may alter metabolism and negatively affect studies using mice. Previous research indicates that nesting...

de Souza Dyer, C., Brice, A. K., Marx, J. O. 2017. Intraperitoneal administration of ethanol as a means of euthanasia for neonatal mice (Mus musculus). JAALAS 56(3), 299-306.

The humane euthanasia of animals in research is of paramount importance. Neonatal mice frequently respond differently to euthanasia agents when compared with adults. The AVMA's Guidelines for the Euthanasia of Animals includes intraperitoneal injection of...

Leduc, R. Y. M., Rauw, G., Baker, G. B. et al. 2017. What goes around can come around: An unexpected deleterious effect of using mouse running wheels for environmental enrichment. JAALAS 56(2), 194-201.

Environmental enrichment items such as running wheels can promote the wellbeing of laboratory mice. Growing evidence suggests that wheel running simulates exercise effects in many mouse models of human conditions, but this activity also might...