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. 
Morello, G. M., Hultgren, J., Capas-Peneda, S. et al. 2020. High laboratory mouse pre-weaning mortality associated with litter overlap, advanced dam age, small and large litters. PLOS ONE 15(8): e0236290.

High and variable pre-weaning mortality is a persistent problem in laboratory mouse breeding. Assuming a modest 15% mortality rate across mouse strains, means that approximately 1 million more pups are produced yearly in the EU...

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...

Zhang, X., Kumstel, S., Tang, G. et al. 2020. A rational approach of early humane endpoint determination in a murine model for cholestasis. ALTEX 37(2), 197-207.

Reduction of animal suffering during in vivo experiments is usually ensured by continuously monitoring the health status using a score sheet and by applying humane endpoints. However, most studies do not evaluate the plausibility of...

Blok, J., Black, D. A., Petersen, J. et al. 2020. Environmental enrichment rescues visually-mediated behavior in Ten-m3 knockout mice during an early critical period. Frontiers in Behavioral Neuroscience 14, 22.

Environmental enrichment (EE) has been shown to promote neural plasticity. Its capacity to induce functional repair in models which exhibit profound sensory deficits due to aberrant axonal guidance has not been well-characterized. Ten-m3 knockout (KO)...

Turner, P. V., Hickman, D. L., van Luijk, J. et al. 2020. Welfare impact of carbon dioxide euthanasia on laboratory mice and rats: A systematic review. Frontiers in Veterinary Science 7, 411.

Background: There has been increased concern about the suitability of CO2 as a method for euthanasia of laboratory mice and rats, including the potential discomfort, pain or distress that animals may experience prior to loss...

Feige-Diller, J., Krakenberg, V., Bierbaum, L. et al. 2020. The effects of different feeding routines on welfare in laboratory mice. Frontiers in Veterinary Science 6, 479.

The accepted norm in most laboratories around the globe is feeding laboratory mice an ad libitum diet, although several health impairments are well-established. In contrast, reducing the animals' body weight by feeding them less food...

Tang, W., Zillmann, U., Sprengel, R. 2020. Alternative anesthesia of neonatal mice for global rAAV delivery in the brain with non-detectable behavioral interference in adults. Frontiers in Behavioral Neuroscience 14, 115.

Viral-transduced gene expression is the current standard for cell-type-specific labeling and cell tacking in experimental neuroscience. To achieve widespread gene expression, a viral delivery method to neonatal rodents was introduced more than two decades ago...

Bengtsson, C., Eriksson, M. 2020. Handling and training of mice and rats results in calmer animals during experimental procedures. AWI Quarterly 69(2) Summer, 6-8.

This article describes the handling and training protocols for mice and rats in preparation for their use in toxicology studies at the Research Institutes of Sweden (RISE).

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...

Stevens, C., Finnegan, E., Clarkson, J. et al. 2020. Report of the 2019 RSPCA/UFAW Rodent Welfare meeting. Animal Technology and Welfare 19(2), 101-111.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 26 years, so that its members can discuss current welfare research, exchange views on welfare issues, and share experiences of...

Singleton, S., Nefla, M., Dennison, N. et al. 2020. Assessing pain in models of rheumatoid arthritis. Animal Technology and Welfare 19(2), 149-152.

A hallmark symptom of rheumatoid arthritis in humans is painful swollen joints. Pain can manifest before any inflammation is noticeable as well as persist long after inflammation has resolved. In rodent models of arthritis, ankle...

Jones, H., King, R. 2020. Refinements to health monitoring. Animal Technology and Welfare 19(2), 153-154.

This poster offers two visual health monitoring scoring sheets for mice. The first consists of a red-amber-green coding system to determine the frequency of daily health checks and when a humane endpoint is reached. The...

Hoskins, S., Brown, J. 2020. Oestrus checking – increasing productivity and embracing the 3R’s. Animal Technology and Welfare 19(2), 159-161.

Much like the menstrual cycle in humans, mice also have a cycle where the eggs ripen, ovulation takes place, the females come into heat and are receptive to mate with the male; this occurs over...

Llaniguez, J. T., Szczepaniak, M. A., Rickman, B. H. et al. 2020. Quantitative and qualitative behavioral measurements to assess pain in axolotls (Ambystoma mexicanum). JAALAS 59(2), 186–196.

Effective pain relief in animals relies on the ability to discern pain and assess its severity. However, few objective measures exist to assess the presence and severity of pain in axolotls, and few resources are...

Smith, B. J., Bruner, K., Hess, A. M. et al. 2020. Female urine-induced ultrasonic vocalizations in male C57BL/6J mice as a proxy indicator for postoperative pain. JAALAS 59(2), 204–211.

Objectively recognizing postoperative pain in mice is challenging, making it difficult to determine an appropriate postoperative analgesic regimen. Adult male mice produce ultrasonic vocalizations after exposure to adult female urine (FiUSV). To determine if FiUSV...

Shomer, N. H., Allen-Worthington, K. H., Hickman, D. L. et al. 2020. Review of rodent euthanasia methods. JAALAS 59(3), 242–253.

The optimal choice of euthanasia method for laboratory rodents depends on a number of factors, including the scientific goals of the study, the need to minimize animal pain and/or distress, applicable guidelines and laws, the...

Laferriere, C. A., Pang, D. S. 2020. Review of intraperitoneal injection of sodium pentobarbital as a method of euthanasia in laboratory rodents. JAALAS 59(3), 254–263.

Euthanasia is one of the most commonly performed procedures in biomedical research, involving tens of millions of animals in North America and Europe every year. The use of sodium pentobarbital, injected intraperitoneally, for killing rodents...

Laferriere, C. A., Leung, V. S., Pang, D. S. 2020. Evaluating intrahepatic and intraperitoneal sodium pentobarbital or ethanol for mouse euthanasia. JAALAS 59(3), 264–268.

Intraperitoneal (IP) injection of sodium pentobarbital (PB) is an accepted method of euthanasia for mice. However, this method has important drawbacks, including the potential for pain or misinjection. The objective of this prospective, randomized, blinded...

Carpenter, K. C., Thurston, S. E., Hoenerhoff, M. J. et al. 2020. Effects of trio and pair breeding of mice on environmental parameters and nasal pathology and their implications for cage change frequency. JAALAS 59(3), 288–297.

According to the Guide, cage change frequencies must be considered when cage density requirements are exceeded. We monitored ammonia, carbon dioxide, cage wetness, health status, and breeding parameters of trio and pair breeding cages containing...

Rix, A., Drude, N., Mrugalla, A. et al. 2020. Performance of severity parameters to detect chemotherapy-induced pain and distress in mice. Laboratory Animals 54(5), 452-460.

According to European Union directive 2010/63/EU a severity classification of experimental procedures performed on laboratory animals is mandatory. This includes a prospective evaluation of all interventions performed within the experiment, as well as an assessment...

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...

Dupepe, L. M., Dauchy, R. T., McAndrew, D. et al. 2020. Eliminating light-at-night contamination during a lab animal facility renovation. Laboratory Animal Science Professional 8(5) (September/October), 60-62.

Relocating laboratory animal research from one animal facility room to another in advance of major renovations can be a daunting task for scientists and animal care personnel alike. This is especially so regarding controlled lighting...

Huang, J., Kayne, P. S. 2020. Buccal swab based genotyping of genetically modified mice. Laboratory Animal Science Professional 8(5) (September/October), 64-66.

Routine sample collection for genotyping genetically modified animals (rodents) (GMAs) typically includes tail snip, toe clip, or ear biopsy. To decrease the potential pain and distress caused by tissue sample collection for genetic analysis, we...

Rodgers, J. C., Ricart Arbona, R. J., Lieggi, C. et al. 2020. Evaluation of cotton dental rolls as environmental enrichment for mice. Laboratory Animal Science Professional 8(5) (September/October), 70-71.

Historically, we provided 2 compressed cotton squares for nesting and enrichment. The logistics of managing nesting material distribution, disposal, and costs are major considerations for our program, which provides husbandry to approximately 60,000 rodent cages...