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. 
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...

Hohlbaum, K., Bert, B., Dietze, S. et al. 2018. Impact of repeated anesthesia with ketamine and xylazine on the well-being of C57BL/6JRj mice. PLOS ONE 13(9), e0203559.

Within the scope of the 3Rs of Russel and Burch, the number of laboratory animals can be reduced by repeated use of an animal. This strategy only becomes relevant, if the total amount of pain...

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...

Hohlbaum, K., Bert, B., Dietze, S. et al. 2017. Severity classification of repeated isoflurane anesthesia in C57BL/6JRj mice—Assessing the degree of distress. PLOS ONE 12(6), e0179588.

According to the EU Directive 2010/63, the severity of a procedure has to be classified as mild, moderate or severe. General anesthesia is thought to be mild, but the Directive does not differentiate between single...

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...

Tavera-Mendoza, L. E., Brown, M. 2017. A less invasive method for orthotopic injection of breast cancer cells into the mouse mammary gland. Laboratory Animals 51(1), 85-88.

Breast cancer is the most common type of cancer diagnosed in women, and the second most common cause of cancer-related deaths in women in North America. The use of laboratory mice in research is an...

Larsen, R. A., Peveler, J. L., Klutzke, J. B. et al. 2017. Effects of daily restraint with and without injections on skeletal properties in C57BL/6NHsd mice. Lab Animal 46(7), 299-301.

Studies typically involve groups of animals that are injected with placebo compounds. As there are studies that demonstrate that restraint and injection can affect behavior and corticosteroid levels in rodents, the basis of such placebo...

Hubbard, J. S., Chen, P. H., Boyd, K. L. 2017. Effects of repeated intraperitoneal injection of pharmaceutical-grade and nonpharmaceutical-grade corn oil in female C57BL/6J mice. JAALAS 56(6), 779-785.

Due to potential adverse effects on animal wellbeing, the use of nonpharmaceutical-grade substances in animal research must be scientifically justified in cases where a pharmaceutical-grade version of the substance exists. This requirement applies to all...

Skorupski, A. M., Zhang, J., Ferguson, D. et al. 2017. Quantification of induced hypothermia from aseptic scrub applications during rodent surgery preparation. JAALAS 56(5), 562-569.

Laboratory mice (Mus musculus) are prone to develop hypothermia during anesthesia for surgery, thus potentially impeding anesthetic recovery, wound healing, and future health. The core body temperatures of isoflurane-anesthetized mice are influenced by the choice...

Chatigny, F., Kamunde, C., Creighton, C. M. et al. 2017. Uses and doses of local anesthetics in fish, amphibians, and reptiles. JAALAS 56(3), 244-253.

Local anesthetics are an integral part of routine pain management in mammals, yet their use is relatively limited in fish, amphibians and reptiles. These animals frequently undergo potentially painful surgical procedures and therefore could possibly...

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...

Parkinson, L., Mans, C. 2017. Anesthetic and postanesthetic effects of alfaxalone–butorphanol compared with dexmedetomidine–ketamine in chinchillas (Chinchilla lanigera). JAALAS 56(3), 290-295.

Effective and safe anesthetic protocols are required for a variety of surgical and diagnostic procedures in chinchillas. Alfaxalone, a new anesthetic agent in the United States, can be administered intramuscularly and subcutaneously and is therefore...

Reiter, C. P., Christy, A. C., Olsen, C. H. et al. 2017. Effect of home cage bedding in the induction chamber on serum cortisol and corticosterone levels in response to isoflurane-induced anesthesia in C57BL/6J mice. JAALAS 56(2), 118-121.

Mice are routinely anesthetized with isoflurane in an induction chamber. The AVMA Guidelines for the Euthanasia of Animals states that distress should be minimized during euthanasia but does not address this point in regard to...

Janssen, C. F., Maiello, P., Wright Jr, M. J. et al. 2017. Comparison of atipamezole with yohimbine for antagonism of xylazine in mice anesthetized with ketamine and xylazine. JAALAS 56(2), 142-147.

The α2 adrenergic agonist xylazine produces a sedative effect and is typically combined with ketamine and used for anesthesia or chemical restraint of laboratory mice. Xylazine's sedative effect—and its undesirable side effects of bradycardia, hypotension...

Wilding, L. A., Hampel, J. A., Khoury, B. M. et al. 2017. Benefits of 21% oxygen compared with 100% oxygen for delivery of isoflurane to mice (Mus musculus) and rats (Rattus norvegicus). JAALAS 56(2), 148-154.

At research institutions, isoflurane delivered by precision vaporizer to a face mask is the standard for rodent surgery and for procedures with durations that exceed a few minutes. Pure oxygen is often used as the...

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...

Palmer, S. 2017. Rescue-Enrich-Release: The environmental enrichment program for three species of captive primates at Colobus. Canopy 17(2), 27-30.

It is widely known that the psychological wellbeing of captive animals can become compromised by a captive environment that lacks proper environmental stimulation. Environmental enrichment programs have become the norm in captive environments yet research...

Alligood, C. A., Dorey, N. R., Mehrkam, L. R. et al. 2017. Applying behavior-analytic methodology to the science and practice of environmental enrichment in zoos and aquariums. Zoo Biology 36(3), 175–185.

Environmental enrichment in zoos and aquariums is often evaluated at two overlapping levels: published research and day‐to‐day institutional record keeping. Several authors have discussed ongoing challenges with small sample sizes in between‐groups zoological research and...

Phillips, B. E., Posner, L. P., Lewbart, G. A. et al. 2017. Effects of alfaxalone administered intravenously to healthy yearling loggerhead sea turtles (Caretta caretta) at three different doses. Journal of the American Veterinary Medical Association 250(8), 909-917.

OBJECTIVE To compare physiologic and anesthetic effects of alfaxalone administered IV to yearling loggerhead sea turtles (Caretta caretta) at 3 different doses. DESIGN Randomized crossover study. ANIMALS 9 healthy yearling loggerhead sea turtles. PROCEDURES Animals...