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. 
Silva-Reis, R., Faustino-Rocha, A. I., Gonçalves, M. et al. 2021. Refinement of animal model of colorectal carcinogenesis through the definition of novel humane endpoints. Animals 11(4), 985.

This study aimed to define appropriate humane endpoints (HEs) for an animal model of colorectal carcinogenesis (CRC). Twenty-nine male Wistar rats were divided into two control groups (CTRL1 and CTRL2) injected with ethylenediamine tetraacetic acid...

Manell, E., Hedenqvist, P., Jensen-Waern, M. 2021. Training pigs for oral glucose tolerance test—Six years’ experience of a refined model. Animals 11(6), 1677.

Animal models of human diseases are important in biomedical research. When using animals for scientific purposes, the 3Rs (replace, reduce, refine) should be considered. Refinement of animal models is essential to ensure best use of...

Nunamaker, E. A., Davis, S., O’Malley, C. I. et al. 2021. Developing recommendations for cumulative endpoints and lifetime use for research animals. Animals 11(7), 2031.

Research animals are important for scientific advancement, and therefore, their long-term welfare needs to be monitored to not only minimize suffering, but to provide positive affective states and experiences. Currently, there is limited guidance in...

Ellis, T., Katsiadaki, I. 2021. Clarification of early end-points for refinement of animal experiments, with specific reference to fish. Laboratory Animals 55(3), 244-253.

Appropriate end-points are integral to the refinement of laboratory animal experiments. Our recent experience has highlighted that ambiguity around end-points is hampering their adoption in experiments that cause severe suffering to fish. In toxicology, the...

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...

Dalla Costa, F. A., Gibson, T. J., Oliveira, S. E.O. et al. 2021. On-farm culling methods used for pigs. Animal Welfare 30(4), 507-522.

The culling of injured and non-viable pigs (Sus scrofa) (neonate to breeding stock) is a routine and necessary procedure on most farms. Usually, pigs are culled using one of the following methods: blunt-force trauma (manual...

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...

Edwards, S. (Ed.) 2021. Understanding the behaviour and improving the welfare of pigs. Burleigh Dodds Science Publishing Limited, Sawston, Cambridge, UK. 594 p.

With growing concern from consumers and regulatory agencies about the welfare of farmed animals such as pigs, the livestock sector must assess how animal welfare can be improved whilst ensuring livestock production remains economically and...

Persson, K., Selter, F., Neitzke, G. et al. 2020. Philosophy of a “good death” in small animals and consequences for euthanasia in animal law and veterinary practice. Animals 10(1), 124.

Moral stress is a major concern in veterinary practice. Often, it is associated with the challenges in end-of-life situations. Euthanasia, however, is also meant to bring relief to animal patients and their owners. The reasons...

Gades, N. M., Thompson, K. L., Mi, L. et al. 2020. Impact of euthanasia on compassion fatigue in personnel working in animal research. Laboratory Animal Science Professional 8(1) (January/February), 22-23.

We conducted a cross-sectional study to investigate the association between euthanasia and compassion fatigue among employees working in animal research at a large academic medical center. In summary, animal research workers who euthanize animals reported...

Talbot, S. R., Biernot, S., Bleich, A. et al. 2020. Defining body-weight reduction as a humane endpoint: A critical appraisal. Laboratory Animals 54(1), 99–110.

In many animal experiments scientists and local authorities define a body-weight reduction of 20% or more as severe suffering and thereby as a potential parameter for humane endpoint decisions. In this study, we evaluated distinct...

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...

Çavuşoğlu, E., Rault, J.-L., Gates, R. et al. 2020. Behavioral response of weaned pigs during gas euthanasia with CO2, CO2 with butorphanol, or nitrous oxide. Animals 10(5), 787.

The swine industry is often forced to euthanize pigs in the first few weeks of life due to injuries, hernias, or unthriftiness. The majority of pigs are euthanized using carbon dioxide (CO2) gas asphyxiation but...

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...

Millecam, J., van Bergen, T., Devreese, M. 2020. Gastrostomy tube placement via a laparotomic procedure in growing conventional piglets to perform multidose preclinical paediatric drug studies. Laboratory Animals 54(3), 261-271.

The use of juvenile conventional pigs as a preclinical animal model to perform pharmacokinetic (PK), pharmacodynamic (PD) and safety studies for the paediatric population is increasing. Repetitive oral administration of drugs to juvenile pigs is...

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...

Helgers, S., Talbot, S. R., Riedesel, A. K. et al. 2020. Body weight algorithm predicts humane endpoint in an intracranial rat glioma model. Scientific Reports 10, 9020.

Humane endpoint determination is fundamental in animal experimentation. Despite commonly accepted endpoint criteria for intracranial tumour models (20% body weight loss and deteriorated clinical score) some animals still die before being euthanized in current research...

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...

Rault, J.-L., Lai, A., Hemsworth, L. et al. 2020. Wireless ‘under the skull’ epidural EEG and behavior in piglets during nitrous oxide or carbon dioxide gas euthanasia. Physiology & Behavior 227, 113142.

Consciousness is central to animal welfare concerns. Its assessment is most often conducted based on behavior, with a poor understanding of the correspondence between behavior and the neurobiological processes that underlie the subjective experience of...

Arruda, A. G., Beyene, T. J., Kieffer, J. et al. 2020. A systematic literature review on depopulation methods for swine. Animals 10(11), 2161.

Swine mass depopulation refers to the destruction of large numbers of pigs and may include not only animals affected with a disease but also healthy pigs in a facility or surrounding areas. Emerging applications of...