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. 
Axiak Flammer, S., Eskes, C., Kohler, I. et al. 2019. Alternatives to carbon dioxide—Taking responsibility for humanely ending the life of animals. Animals 9(8), 482.

Carbon dioxide (CO2) is commonly used to kill rodents. However, a large body of research has now established that CO2 is aversive to them. A multidisciplinary symposium organized by the Swiss Federal Food Safety and...

Steiner, A. R., Axiak Flammer, S., Beausoleil, N. J. et al. 2019. Humanely ending the life of animals: Research priorities to identify alternatives to carbon dioxide. Animals 9(11), 911.

The use of carbon dioxide (CO2) for stunning and killing animals is considered to compromise welfare due to air hunger, anxiety, fear, and pain. Despite decades of research, no alternatives have so far been found...

Dutton III, J. W., Artwohl, J. E., Huang, X. et al. 2019. Assessment of pain associated with the injection of sodium pentobarbital in laboratory mice (Mus musculus). JAALAS 58(3), 373-379.

The AVMA Guidelines for the Euthanasia of Animals considers injection of barbiturates to be an acceptable method of euthanasia in rodents but states there is a potential for pain when administered intraperitoneally. This study examined...

Moffitt, A. D., Brignolo, L. L., Ardeshir, A. et al. 2019. The role of emotional contagion in the distress exhibited by grouped mice exposed to CO2. JAALAS 58(4), 430-437.

The 2013 AVMA Guidelines for the Euthanasia of Animals recommends a chamber volume displacement rate of 10% to 30% per minute (v/min) when euthanizing small laboratory rodents with CO2. Group euthanasia of mice is a...

Dunford, K., Hakkesteeg, J., Wilson, C. 2019. Stiff as a board: Measuring rigor mortis in zebrafish. Animal Technology and Welfare 18(3), 203-205.

Schedule one killing (S1K) methods require a two-step process: a humane method of death, typically for Zebrafish an anaesthetic overdose and confirmation of death, such as confirmation of rigor mortis. There is widespread variation of...

Jirkof, P., Rudeck, J., Lewejohann, L. 2019. Assessing affective state in laboratory rodents to promote animal welfare—What is the progress in applied refinement research? Animals 9(12), 1026.

In the past, there was a strong focus on avoiding or reducing negative animal welfare in animal experimentation. Recently, the importance of promoting positive animal welfare in laboratory animals has been highlighted. To ensure and...

McMillan, F. D. (ed). 2019. Mental Health and Well-being in Animals (2nd ed). CABI, Wallingford, UK.

This second edition is fully revised, expanded, and comprehensively updated with the most current knowledge about the full array of mental health issues seen in animals. Written by key opinion leaders, internationally-recognized experts and specialists...

Thurman, C. E., Rasmussen, S., Prestia, K. A. 2019. Effect of 3 euthanasia methods on serum yield and serum cortisol concentration in zebrafish (Danio rerio). JAALAS 58(6), 823–828.

Zebrafish are an important model in neuroscience and developmental biology and are also an emerging model in hematology and immunology. Little information is available for zebrafish regarding the physiologic impact of different euthanasia methods and...

Gent, T. C., Detotto, C., Vyssotski, A. L. et al. 2018. Epileptiform activity during inert gas euthanasia of mice. PLOS ONE 13(4), e0195872.

Carbon dioxide (CO2) is one of the most commonly used euthanasia agents for mice, yet it is highly aversive and nociceptive. Inert gases are a possible alternative, however there are qualitative reports of seizures resulting...

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...

Wallace, C. K., Bright, L. A., Marx, J. O. et al. 2018. Effectiveness of rapid cooling as a method of euthanasia for young zebrafish (Danio rerio). JAALAS 57(1), 58-63.

Despite increased use of zebrafish (Danio rerio) in biomedical research, consistent information regarding appropriate euthanasia methods, particularly for embryos, is sparse. Current literature indicates that rapid cooling is an effective method of euthanasia for adult...

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...

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...

Bailoo, J. D., Murphy, E., Varholick, J. A. et al. 2018. Evaluation of the effects of space allowance on measures of animal welfare in laboratory mice. Scientific Reports 8, 713.

We studied how space allowance affects measures of animal welfare in mice by systematically varying group size and cage type across three levels each in both males and females of two strains of mice (C57BL/6ByJ...

Franks, B., Graham, C., Von Keyserlingk, M. A. G. 2018. Is heightened-shoaling a good candidate for positive emotional behavior in zebrafish? Animals 8(9), 152.

Zebrafish, a highly-social species of freshwater fish, are widely studied across many fields of laboratory science including developmental biology, neuroscience, and genomics. Nevertheless, as standard housing for zebrafish typically consists of small and simplistic environments...

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...

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...

Köhler, A., Collymore, C., Finger-Baier, K. et al. 2017. Report of Workshop on Euthanasia for Zebrafish—A Matter of welfare and science. Zebrafish 14(6), 547-551.

The increasing importance of zebrafish as a biomedical model organism is reflected by the steadily growing number of publications and laboratories working with this species. Regulatory recommendations for euthanasia as issued in Directive 2010/63/EU are...

Walsh, J., Percival, A., Turner, P. 2017. Efficacy of blunt force trauma, a novel mechanical cervical dislocation device, and a non-penetrating captive bolt device for on-farm euthanasia of pre-weaned kits, growers, and adult commercial meat rabbits. Animals 7(12), 100.

The commercial meat rabbit industry is without validated on-farm euthanasia methods, potentially resulting in inadequate euthanasia protocols. We evaluated blunt force trauma (BFT), a mechanical cervical dislocation device (MCD), and a non-penetrating captive bolt device...

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...

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...

Boivin, G. P., Bottomley, M. A., Schiml, P. A. et al. 2017. Physiologic, behavioral, and histologic responses to various euthanasia methods in C57BL/6NTac male mice. JAALAS 56(1), 69-78.

Rodent euthanasia using exposure to increasing concentrations of CO2 has come under scrutiny due to concerns of potential pain during the euthanasia process. Alternatives to CO2, such as isoflurane and barbiturates, have been proposed as...

Polissidis, A., Zelelak, S., Nikita, M. et al. 2017. Assessing the exploratory and anxiety-related behaviors of mice. Do different caging systems affect the outcome of behavioral tests? Physiology & Behavior 177, 68-73.

Ample studies have shown that housing can affect the health, welfare and behavior of mice and therefore, the outcomes of certain experiments. The aim of this study was to investigate if three widely used housing...

Mortell, D., Moores, S. 2017. Increasing survival rates in the Zebrafish (Zebra danio) at the University of Manchester. Animal Technology and Welfare 16(3), 214-215.

The average survival rate for our Zebrafish (ZF) embryos was 65%. When it was time to create our next generation of Wild Type (WT) (used for embryo production), we decided to run a trial focussing...

Guedes, S. R., Valentim, A. M., Antunes, L. M. 2017. Mice aversion to sevoflurane, isoflurane and carbon dioxide using an approach-avoidance task. Applied Animal Behaviour Science 189, 91-97.

Euthanasia of laboratory animals is one of the main concerns for animal welfare, especially the use of carbon dioxide (CO2) which has been described to induce aversive-like behaviours. In order to refine mass euthanasia in...