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. 
Perret-Thiry, C., Raulic, J., Vergneau-Grosset, C. 2022. Evaluation of prolonged immersion in tricaine methanesulfonate for juvenile goldfish (Carassius auratus) euthanasia. Journal of the American Veterinary Medical Association 260(8), 911-915.

OBJECTIVE: Doses of buffered tricaine methanesulfonate (MS-222) up to 1000 mg/L for 15 minutes are reported inefficient to produce euthanasia in goldfish. The goal of this study was to determine if goldfish can be euthanized...

LaFollette, M. R. 2022. Refined ways to pick up mice. Laboratory Animal Science Professional 10(2) (March/April), 46-48.

As part of our commitment to continuous improvement of laboratory animal welfare, the North American 3Rs Collaborative (NA3RsC) brought together several experts to examine the evidence, impact, and practicality of alternative methods for picking up...

Hull, M. A., Reynolds, P. S., Nunamaker, E. A. 2022. Effects of non-aversive versus tail-lift handling on breeding productivity in a C57BL/6J mouse colony. PLOS ONE 17(1), e0263192.

Non-aversive handling is a well-documented refinement measure for improving rodent welfare. Because maternal stress is related to reduced productivity, we hypothesized that welfare benefits associated with non-aversive handling would translate to higher production and fewer...

Bartlett, J., Davies, J., Purawijaya, D. et al. 2022. Refinement of handling and dosing methods for rats and mice. Animal Technology and Welfare 21(2), 120-124.

Modified Handling for Mice: Handling mice by gripping the base of the tail has been shown to negatively impact animal welfare by increasing anxiety and aversion to handling. We aimed to refi ne the dosing...

Davies, J. R., Purawijaya, D. A., Bartlett, J. M. et al. 2022. Impact of refinements to handling and restraint methods in mice. Animals 12(17), 2173.

There is increasing evidence that, compared to non-aversive handling methods (i.e., tunnel and cupping), tail handling has a negative impact on mouse welfare. Despite this evidence, there are still research organisations that continue to 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...

Zausinger, P., Schneider, B. M., Bauer, A. et al. 2022. Short communication: Do the tameness of the dams and the sex of the offspring have an influence on the “gentling” effect in laboratory rats? Journal of Veterinary Behavior 52-53, 45-49.

“Gentling” (soft touching, “taming”) has long-term effects on the behavior of laboratory rats (Rattus norvegicus). Our own studies showed that the use of a “gentling” program in the fourth and fifth week of life resulted...

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...

Hwang, S.-K., Tyszkiewicz, C., Dragon, M. et al. 2022. Introduction of gloved hand to cage induces 22-kHz ultrasonic vocalizations in male albino rats. PLOS ONE 17(11), e0278034.

Rodents emit ultrasonic vocalizations (USVs) above the human hearing threshold of ~ 20 kHz to communicate emotional states and to coordinate their social interactive behavior. Twenty-two kHz USVs emitted by adult rats have been reported...

Novak, J., Jaric, I., Rosso, M. et al. 2022. Handling method affects measures of anxiety, but not chronic stress in mice. Scientific Reports 12(1), 20938.

Studies in mice have shown that less aversive handling methods (e.g. tunnel or cup handling) can reduce behavioural measures of anxiety in comparison to picking mice up by their tail. Despite such evidence, tail handling...

Assenmacher, C.-A., Lanza, M., Tarrant, J. C. et al. 2022. Post mortem study on the effects of routine handling and manipulation of laboratory mice. Animals 12(23), 3234.

Routine handling and manipulation of laboratory mice are integral components of most preclinical studies. Any type of handling and manipulation may cause stress and result in physical harm to mice, potentially leading to unintended consequences...

Nuber, M., Gonzalez-Uarquin, F., Neufurth, M. et al. 2022. Development of a 3D simulator for training the mouse in utero electroporation. PLOS ONE 17(12), e0279004.

In utero electroporation (IUE) requires high-level training in microinjection through the mouse uterine wall into the lateral ventricle of the mouse brain. Training for IUE is currently being performed in live mice as no artificial...

Prentice, P. M., Houslay, T. M., Wilson, A. J. 2022. Exploiting animal personality to reduce chronic stress in captive fish populations. Frontiers in Veterinary Science 9, 1046205.

Chronic stress is a major source of welfare problems in many captive populations, including fishes. While we have long known that chronic stress effects arise from maladaptive expression of acute stress response pathways, predicting where...

Torgerson-White, L., Sánchez-Suárez, W. 2022. Looking beyond the shoal: Fish welfare as an individual attribute. Animals 12(19), 2592.

Welfare is an individual attribute. In general, providing captive nonhuman animals with conditions conducive to good welfare is an idea more easily applied when dealing with few individuals. However, this becomes much harder—if not impossible—under...

Brough, D. W., Murkin, J. T., Amos, H. E. et al. 2022. Comparing variability in measurement of subcutaneous tumors in mice using 3D thermal imaging and calipers. Comparative Medicine 72(6), 364–375.

Repeatable tumor measurements are key to accurately assessing tumor growth and treatment efficacy. A preliminary study that we conducted showed that a novel 3D and thermal imaging system (3D-TI) for measuring subcutaneous tumors in rodents...

Gresham, C., Mathews, F., Ferguson, A. et al. 2022. Does handling for public talks in zoos affect the behaviour of captive Mexican red-kneed spiders Brachypelma hamorii? Journal of Zoological and Botanical Gardens 3(2), 158–169.

Zoos include invertebrates in visitor interaction sessions to educate and spread conservation messages to the public. Yet, the welfare implications of these encounters on invertebrates are unstudied. Empirical studies reveal negative effects of handling on...

Hepps Keeney, C., Harrison, T. M. 2022. Euthanasia complications in non-domestic species. Journal of Zoological and Botanical Gardens 3(4), 616–623.

There are very few studies describing euthanasia complications in non-domestic species. The goal of this study was to survey veterinarians to determine what complications may commonly occur during the euthanasia of non-domestic species. An online...

Suba-Bokodi, É., Nagy, I., Molnár, M. 2022. Changes in the stress tolerance of dwarf rabbits in animal-assisted interventions. Applied Sciences 12(14), 6979.

Background: Rabbits are common companion animals in many European countries. Rabbit-assisted interventions in primary schools are suitable for decreasing the anxiety levels of children, which may increase the education efficiency of teachers. Methods: In our...

Ikeya, K., Torisawa, S., Yamane, H. et al. 2022. Estimating the total length of Mekong giant catfish, Pangasianodon gigas, in an aquarium via stereo-video shooting and direct linear transformation. Zoo Biology 41(6), 554–559.

The Mekong giant catfish (MGC), Pangasianodon gigas, is one of the world’s largest catfish species. Endemic to the Mekong River system, the MGC is critically endangered. Six MGC were transported from Thailand to the Gifu...

Zeng, Y., Jin, H., Wang, J. et al. 2022. An optimized method for intratracheal instillation in mice. Journal of Pharmacological and Toxicological Methods 118, 107230.

Non-invasive intratracheal instillation is an important method for direct exposure of the respiratory tract which is commonly used in toxicology, environmental science, and other research fields. However, there is no standard operating process for non-invasive...

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...

Sørensen, D., Cloutier, S., Gaskill, B. (Eds.). 2021. Animal-centric Care and Management - Enhancing Refinement in Biomedical Research. CRC Press, Boca Raton, FL.

The concept of the 3Rs (Refinement, Reduction and Replacement) has been used as a framework for improving the welfare of laboratory animals for the last half century. By establishing an animal-centric view on housing and...

Stevens, C., Hawkins, P., Smulders, T. V. et al. 2021. Report of the 2020 RSPCA/UFAW rodent and rabbit welfare meeting. Animal Technology and Welfare 20(1), 21-33.

The RSPCA/UFAW rodent and rabbit welfare group has held a one-day meeting every autumn for the last 27 years, so that its members can discuss current welfare research, exchange views on welfare issues and share...