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. 
Golledge, H., Richardson, C. (Eds.) 2024. The UFAW Handbook on the Care and Management of Laboratory and Other Research Animals (9th ed.). Wiley-Blackwell. 1040 p.

The latest edition of the seminal reference on the care and management of laboratory and research animals. The newly revised ninth edition of The UFAW Handbook on the Care and Management of Laboratory and Other...

Peruga, M., Kawala, B., Sarul, M. et al. 2023. Are currently selected laboratory animals useful in the research of how female hormones influence orthodontic biomechanics? Animals 13(4), 629.

Animal testing was and remains the only method of introducing a certain treatment and medical procedure on humans. On the other hand, animals have their rights resulting from applicable legal acts, including Directive 2010/63/EU and...

Domínguez-Oliva, A., Hernández-Ávalos, I., Olmos-Hernández, A. et al. 2023. Thermal response of laboratory rats (Rattus norvegicus) during the application of six methods of euthanasia assessed by infrared thermography. Animals 13(18), 2820.

Refinement is one of the principles aiming to promote welfare in research animals. The techniques used during an experimental protocol, including euthanasia selection, must prevent and minimize suffering. Although the current euthanasia methods applied to...

Domínguez-Oliva, A., Olmos-Hernández, A., Hernández-Ávalos, I. et al. 2023. Rat grimace scale as a method to evaluate animal welfare, nociception, and quality of the euthanasia method of wistar rats. Animals 13(20), 3161.

Refinement of experimental procedures in animal research has the objective of preventing and minimizing pain/distress in animals, including the euthanasia period. This study aimed to evaluate pain associated with six methods of euthanasia in Wistar...

Klabukov, I., Shestakova, V., Krasilnikova, O. et al. 2023. Refinement of animal experiments: Replacing traumatic methods of laboratory animal marking with non-invasive alternatives. Animals 13(22), 3452.

Reliable methods for identifying rodents play an important role in ensuring the success of preclinical studies. However, animal identification remains a trivial laboratory routine that is not often discussed, despite the fact that more than...

Stevens, C., Hammonds, T., Hinchcliffe, J. et al. 2023. Report of the 2022 RSPCA/UFAW Rodent Welfare Group Meeting. Animal Technology and Welfare 22(2), 91–100.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 29 years, so that its members can discuss current welfare research, exchange views on welfare issues and share experiences of...

Van Loo, P. L. P., Janssens, M. R. E. 2023. Why all healthy laboratory animals should be rehomed, no matter how small. Animals 13(17), 2727.

This paper explores the ethical imperative of rehoming all healthy animals of sentient species after experiments have finished or when they have become otherwise redundant. We take into account disparate perspectives in animal ethics and...

Munro, B. A., Merenick, D. R., Gee, J. M. et al. 2023. Use of loss of righting reflex to assess susceptibility to carbon dioxide gas in three mouse strains. JAALAS 62(6), 553–558.

Exposure to CO2 gas is a common rodent euthanasia method. CO2 activates nociceptors in rats and is painful to humans at concentrations equal to or greater than 32.5% The concentration of CO2 at which rodents...

Chen, D. D., Molk, D. M., Palley, L. S. et al. 2023. Pinna edge biopsy of 7 and 21 day old C57BL/6 mice as a method for identification and genotyping. JAALAS 62(5), 438–448.

Identifying and genotyping mice prior to weaning can be useful for mouse colony management. Mice of an undesired genotype can be identified prior to weaning and removed from further study, resulting in a reduction of...

Hickman, D. L. 2023. Euthanasia of neonatal rats and mice using carbon monoxide. JAALAS 62(3), 274–278.

Minimization of potential pain and distress of rodents undergoing euthanasia is a touchstone of veterinary clinical medicine. Evaluation of this issue in postweanling rodents has supported revisions to the AVMA (American Veterinary Medical Association) Guidelines...

McNamara, A., Ballantine, A. R., Deuchande, R. et al. 2023. Comparison of fixed and rising displacement rates of CO2 for euthanasia of aged rats. JAALAS 62(5), 453–463.

This study compared euthanasia induced by rising concentrations of CO2 in aged rats (n = 59) using different gas displacement rates. Rats were preimplanted with cardiovascular telemetry devices and had been previously used for short...

Stuckey, J. E., Makhija, S. D., Reimer, D. C. et al. 2023. Effects of different grades of carbon dioxide on euthanasia of mice (Mus musculus). JAALAS 62(5), 430–437.

Carbon dioxide (CO2) is a conditionally acceptable method for mouse euthanasia, according to the American Veterinary Medical Association Guidelines for the Euthanasia of Animals. In a 2012 Office of Laboratory Animal Welfare (OLAW) webinar, representatives...

Hickman, D. L. 2022. Evaluation of carbon dioxide euthanasia of female Sprague Dawley rats alone or with unfamiliar conspecifics. JAALAS 61(2), 195-200.

Most studies evaluating methods of euthanasia to date have focused on the euthanasia of individual animals. However, larger chambers are commonly used to euthanize multiple cages of animals at once. This study evaluated the use...

Hickman, D. L. 2022. Minimal exposure times for irreversible euthanasia with carbon dioxide in mice and rats. JAALAS 61(3), 283-286.

When using an anesthetic overdose to euthanize laboratory rodents, a secondary method of euthanasia is recommended to ensure that the apparent death is irreversible. This secondary method usually is accomplished through the collection of tissues...

McKinney, M. M., Dupont, W. D., Corson, K. J. et al. 2022. Physiologic and behavioral effects in mice anesthetized with isoflurane in a red-tinted or a traditional translucent chamber. JAALAS 61(4), 322-332.

Isoflurane has been characterized as a distressing agent for rodents, causing both physiologic and behavioral effects. Using a "darkened home cage" has been recommended during CO2 administration for rodent euthanasia; this is arguably a similar...

Clarkson, J. M., Martin, J. E., McKeegan, D. E. F. 2022. A review of methods used to kill laboratory rodents: Issues and opportunities. Laboratory Animals 56(5), 419-436.

Rodents are the most widely used species for scientific purposes. A critical pre-requisite of their use, based on utilitarian ethical reasoning, is the provision of a humane death when necessary for scientific or welfare grounds...

Hickman, D. L. 2021. Wellbeing of mice euthanized with carbon dioxide in their home cage as compared with an induction chamber. JAALAS 60(1), 72-76.

The AVMA Guidelines on Euthanasia state that, to decrease potential distress of animals, the home cage should be used for the euthanasia of mice. The current study evaluated this recommendation by comparing behavioral and physiologic...

Améndola, L., Ratuski, A., Weary, D. M. 2021. Individual differences in rat sensitivity to CO2. PLOS ONE 16(1), e0245347.

Feelings of fear, anxiety, dyspnea and panic when inhaling carbon dioxide (CO2) are variable among humans, in part due to differences in CO2 sensitivity. Rat aversion to CO2 consistently varies between individuals; this variation in...

Carbone, L. 2021. Estimating mouse and rat use in American laboratories by extrapolation from Animal Welfare Act-regulated species. Scientific Reports 11(1), 493.

Alone among Western nations, the United States has a two-tier system for welfare protections for vertebrate animals in research. Because its Animal Welfare Act (AWA) excludes laboratory rats and mice (RM), government veterinarians do not...

Kammertoens, T., Jeuthe, S., Baranzke, H. et al. 2021. Breeding and maintenance of immunodeficient mouse lines under SPF conditions—A call for individualized severity analyses and approval procedures. Animals 11(6), 1789.

In the EU, the breeding of genetically modified laboratory animals is, by definition, an animal experiment if the offspring may experience pain, suffering, or harm. In order to determine the actual burden of genetically modified...

Burn, C. C., Mazlan, N. H. B., Chancellor, N. et al. 2021. The pen is milder than the blade: Identification marking mice using ink on the tail appears more humane than ear-punching even with local anaesthetic. Animals 11(6), 1664.

Identification marking mice commonly involves ear-punching with or without anaesthetic, or tail-marking with ink. To identify which is most humane, we marked weanling male BALB/c mice using ear-punching (EP), ear-punching with anaesthetic EMLATM cream (EP+A)...

Rodriguez-Sanchez, R., Barnaby, E., Améndola, L. et al. 2021. Voluntary oral ingestion of a sedative prior to euthanasia with CO2: Behavioural responses of mice. Animals 11(10), 2879.

Laboratory mice are commonly euthanised with carbon dioxide (CO2); however, there is ample evidence that this gas is aversive. Previous work suggests that sedation achieved via injection with benzodiazepines prior to CO2 administration could reduce...

Brunt, M. W., Améndola, L., Weary, D. M. 2021. Attitudes of laboratory animal professionals and researchers towards carbon dioxide euthanasia for rodents and perceived barriers to change. Laboratory Animals 55(6), 531-539.

Evidence indicates that carbon dioxide (CO2) induces negative affective states (including anxiety, fear and distress) in laboratory rodents, but many countries still accept it for euthanasia. Alternative methods (e.g. inhalant anaesthetic) may represent a refinement...

Young, T., Whiteside, T., Locklear, J. 2020. What is your tattoo ink telling you? Laboratory Animal Science Professional 8(2) (March/April), 62-65.

Tattooing traumatizes the skin, which can result in microbial infections with the severity ranging from minor to life-threating septicemia. Additionally, the metals in colored tattoo ink are known to cause dermal inflammation in some people...

Składanowska-Baryza, J., Ludwiczak, A., Pruszyńska-Oszmałek, E. et al. 2020. Effect of two different stunning methods on the quality traits of rabbit meat. Animals 10(4), 700.

The aim of the study was to assess the effect of two different stunning methods on the level of blood stress indicators (cortisol, insulin, glucose) and rabbit meat quality. The experiment was conducted on crossbreds...