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. 
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...

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...

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...

Galex, I. A., Gallant, C. M., D'Avignon, N. et al. 2020. Evaluation of effective and practical euthanasia methods for larval African clawed frogs (Xenopus laevis). JAALAS 59(3), 269–274.

Larval, or tadpole-stage Xenopus laevis frogs are a popular research model for developmental biology and disease studies. Existing euthanasia guidance documents offer recommendations for both eggs and adult stages, yet do not specifically address the...

Natusch, D. J. D., Aust, P. W., Khadiejah, S. et al. 2020. Behavioral and corticosterone responses to carbon dioxide exposure in reptiles. PLOS ONE 15(10), e0240176.

The use of carbon dioxide (CO2) exposure as a means of animal euthanasia has received considerable attention in mammals and birds but remains virtually untested in reptiles. We measured the behavioral responses of four squamate...

Scarborough, J., Mueller, F., Arban, R. et al. 2020. Preclinical validation of the micropipette-guided drug administration (MDA) method in the maternal immune activation model of neurodevelopmental disorders. Brain, Behavior, and Immunity 88, 461-470.

Pharmacological treatments in laboratory rodents remain a cornerstone of preclinical psychopharmacological research and drug development. There are numerous ways in which acute or chronic pharmacological treatments can be implemented, with each method having certain advantages...

Woodard, C. L., Nasrallah, W. B., Samiei, B. V. et al. 2020. PiDose: An open-source system for accurate and automated oral drug administration to group-housed mice. Scientific Reports 10, 11584.

Drug treatment studies in laboratory mice typically employ manual administration methods such as injection or gavage, which can be time-consuming to perform over long periods and cause substantial stress in animals. These stress responses may...

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...

Stevens, C., Hawkins, P., Lovell-Badge, R. et al. 2019. Report of the 2018 RSPCA/UFAW Rodent and Rabbit Welfare Group meeting. Animal Technology and Welfare 18(2), 81-91.

The RSPCA/UFAW Rodent (and now Rabbit) Working Group has held a one-day meeting every autumn for the last 25 years, so that its members can discuss current welfare research, exchange views on welfare issues and...

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...

Windsor, Z., Bate, S. T. 2019. Assessing the safety and suitability of nesting material for singly housed mice with surgically fitted head plates. Heliyon 5(7), e02097.

Nesting material, for example shredded paper, is a common form of enrichment for laboratory mice. However, there has been limited research performed regarding its apparent safety when given to mice fitted with exteriorised devices such...

Gjendal, K., Lund Ottesen, J., Olsson, I. A. S. et al. 2019. Burrowing and nest building activity in mice after exposure to grid floor, isoflurane or ip injections. Physiology & Behavior 206, 59-66.

Burrowing and nest building are examples of highly motivated innate behaviours in rodents. Assessments based on these behaviours can be used as non-invasive indicators of pain, distress and suffering. In this study, we investigated the...

Ritchie, A., Collier, P., Clare, P. et al. 2019. Food for thought: The development of drug loaded diets improve both science and welfare. Animal Technology and Welfare 18(3), 222-224.

In our facility, we use several hormone dependent tumour models with supplementation delivered via slow release subcutaneously implanted pellets, implanted via trochar. For example, breast tumours which rely on 17-β-Estradiol. Administration of E2 supplementation can...

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...

Santurtun, E., Broom, D. M., Phillips, C. J. C. 2018. A review of factors affecting the welfare of Atlantic salmon (Salmo salar). Animal Welfare 27(3), 193-204.

In the expanding salmon industry, many farmers use production methods that could result in poor welfare of the fish at various points of their lifecycle. We have reviewed methods used for producing salmon for food...

Golledge, H., Carter, E. 2018. Welfare of fish farmed in the EU during transport and at slaughter. Animal Welfare 27(3), 287-288.

This Report, commissioned by the European Commission, summarises the current state of transport and slaughter practices in the aquaculture industry within eleven case-study countries in the European Economic Area (EAA). Comparisons are also made with...

Deurinck, M., Schindler, S., Bugnon, P. et al. 2018. Report from the 2017 Annual SGV (Swiss Laboratory Animal Science Association ) Meeting. Laboratory Animals 52(2), 211-213. [Meeting Report]

The Scientific Committee of the Swiss Laboratory Animal Science Association (Schweizerische Gesellschaft für Versuchstierkunde, SGV) reports on the Annual SGV Meeting held on 28 and 29 November 2017, at Technopark, Zürich, Switzerland. Feedback after the...

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...

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...

Galvin, M., Lallo, A., Brown, S. et al. 2018. Refinement of tumour passage by optimisation of the tissue disaggregation protocol. Animal Technology and Welfare 17(2), 101-103.

Surgical implantation of tumour pieces has been used regularly in the passage of tumour models. This involves an invasive surgical procedure, carried out under anaesthesia, ensuring mice have adequate pain relief and peri-operative care. The...

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...