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. 
Wahltinez, S. J., Stacy, N. I., Hadfield, C. A. et al. 2022. Perspective: Opportunities for advancing aquatic invertebrate welfare. Frontiers in Veterinary Science 9, 973376.

Welfare considerations and regulations for invertebrates have lagged behind those for vertebrates, despite invertebrates comprising more than 95% of earth’s species. Humans interact with and use aquatic invertebrates for exhibition in zoos and aquaria, as...

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...

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...

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...

Conte, F., Voslarova, E., Vecerek, V. et al. 2021. Humane slaughter of edible decapod crustaceans. Animals 11(4), 1089.

Vast numbers of crustaceans are produced by aquaculture and caught in fisheries to meet the increasing demand for seafood and freshwater crustaceans. Simultaneously, the public is increasingly concerned about current methods employed in their handling...

Wahltinez, S. J., Kroll, K. J., Nunamaker, E. A. et al. 2021. Practical euthanasia method for common sea stars (Asterias rubens) that allows for high-quality RNA sampling. Animals 11(7), 1847.

Sea stars in research are often lethally sampled without available methodology to render them insensible prior to sampling due to concerns over sufficient sample quality for applied molecular techniques. The objectives of this study were...

Satokar, V., Vickers, M., Bridge-Comer, P. et al. 2021. Emulsified gels: A refined vehicle for accurate and rapid oral administration of lipid based preparations to rats. Animal Technology and Welfare 20(2), 95-103.

Oro-gastric gavage is used to accurately administer nutritional substances or drugs to animals. However, it induces stress and has a substantial risk of mishap. Incorporation into edible gels is difficult for lipid-based preparations. We report...

Kay, W. R., Mawson, P. R. 2021. An efficient method for the euthanasia of cane toads (Rhinella marina) under northern Australian field conditions. Animals 11(8), 2239.

The euthanasia of cane toads under field conditions presents a number of logistical and animal welfare challenges. One recommended method of control involves the use of carbon dioxide in plastic bags. This paper describes the...

Zemanova, M. A. 2021. Noninvasive genetic assessment is an effective wildlife research tool when compared with other approaches. Genes 12(11), 1672.

Wildlife research has been indispensable for increasing our insight into ecosystem functioning as well as for designing effective conservation measures under the currently high rates of biodiversity loss. Genetic and genomic analyses might be able...

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...

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...

Frost, K., Shah, M., Leung , V. S. Y. et al. 2020. Aversion to desflurane and isoflurane in Sprague-Dawley rats (Rattus norvegicus). Animals 10(6), 950.

Carbon dioxide and isoflurane are widely used for killing rats, yet may not truly achieve “euthanasia”, because they elicit aversion. The inhalant anesthetic desflurane is faster acting than isoflurane, representing a potential refinement. Using an...

Forrest, G., Sattar, A., Evenden, P. et al. 2020. A sweet change to the needle. Animal Technology and Welfare 19(1), 73-75.

The Named Veterinary Surgeon (NVS) at the Royal Veterinary College in London suggested providing post-operative pain relief (carprofen) to rats in raspberry flavoured jelly to avoid the use of s.c. injections. This article provides a...

Ballantine, A., Rodgers, D., Watts, C. et al. 2020. The cotton rat – a new challenge. Animal Technology and Welfare 19(1), 92-95.

This poster describes how the Animal Technologists at Envigo adapted their current practices and procedures for a new species at their laboratory: the cotton rat. The paper describes cotton rat biology and behaviour; housing; environmental...

Améndola, L., Weary, D. M. 2020. Understanding rat emotional responses to CO2. Translational Psychiatry 10, 253.

The aim of this review is to summarize evidence regarding rat emotional experiences during carbon dioxide (CO2) exposure. The studies reviewed show that CO2 exposure is aversive to rats, and that rats respond to CO2...

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...

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...

Tilley, C. A., Carreño Gutierrez, H., Sebire, M. et al. 2020. Skin swabbing is a refined technique to collect DNA from model fish species. Scientific Reports 10(1), 18212.

Model fish species such as sticklebacks and zebrafish are frequently used in studies that require DNA to be collected from live animals. This is typically achieved by fin clipping, a procedure that is simple and...

Cohen, S., Kwok, M., Huang, J. 2020. Humane euthanasia of guinea pigs (Cavia porcellus) with a penetrating spring-loaded captive bolt. Animals 10(8), 1356.

Guinea pigs (Cavia porcellus) have been used in research since the 19th century to collect data due to their physiological similarities to humans. Today, animals perform a vital role in experiments and concerns for laboratory...

Kulkarni, S., Hickman, D. 2020. Isoflurane and carbon dioxide elicit similar behavioral responses in rats. Animals 10(8), 1431.

Euthanasia in rodents is an ongoing topic of debate due to concerns regarding the aversive nature of gases with anesthetic properties such as carbon dioxide (CO2) and isoflurane. The aim of this study was to...

Pedrazzani, A. S., Quintiliano, M. H., Bolfe, F. et al. 2020. Tilapia on-farm welfare assessment protocol for semi-intensive production systems. Frontiers in Veterinary Science 7, 606388.

The aim of this study was to develop and test a tilapia on-farm welfare assessment protocol, based on Brazilian semi-intensive production systems. The study included two mains steps: the elaboration of tilapia welfare protocol and...