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. 
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...

Balafas, E., Stasinopoulou, M., Alexakos, P. et al. 2018. Synchronisation of oestrous cycle on C57BL/6J mice after the introduction of a hanging perforated container with bedding soaked by the excretions of male mice. Animal Technology and Welfare 17(1), 9-11.

Synchronisation of oestrous cycle is a commonly used method to manage pregnancies either for breeding or for research purposes. Based on Whitten effect, the aim of our study was to introduce a new refined method...

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...

Toth, L. A. 2018. Identifying and implementing endpoints for geriatric mice. Comparative Medicine 68(6), 439–451.

The types of changes in physical appearance and behavior that occur in elderly people similarly develop in elderly animals. Signs and symptoms that might cause concern in younger people or mice may be normal in...

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...

Tavera-Mendoza, L. E., Brown, M. 2017. A less invasive method for orthotopic injection of breast cancer cells into the mouse mammary gland. Laboratory Animals 51(1), 85-88.

Breast cancer is the most common type of cancer diagnosed in women, and the second most common cause of cancer-related deaths in women in North America. The use of laboratory mice in research is an...

Larsen, R. A., Peveler, J. L., Klutzke, J. B. et al. 2017. Effects of daily restraint with and without injections on skeletal properties in C57BL/6NHsd mice. Lab Animal 46(7), 299-301.

Studies typically involve groups of animals that are injected with placebo compounds. As there are studies that demonstrate that restraint and injection can affect behavior and corticosteroid levels in rodents, the basis of such placebo...

Hubbard, J. S., Chen, P. H., Boyd, K. L. 2017. Effects of repeated intraperitoneal injection of pharmaceutical-grade and nonpharmaceutical-grade corn oil in female C57BL/6J mice. JAALAS 56(6), 779-785.

Due to potential adverse effects on animal wellbeing, the use of nonpharmaceutical-grade substances in animal research must be scientifically justified in cases where a pharmaceutical-grade version of the substance exists. This requirement applies to all...

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...

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...

Wallace, P. Y., Asa, C. S., Agnew, M. et al. 2016. A review of population control methods in captive-housed primates. Animal Welfare 25(1), 7-20.

The success of breeding primates in captivity has led to a surplus number of animals in collections. This review examines published journals and key books to investigate the various methods of primate population control. Hormonal...

Norton, W. B., Scavizzi, F., Smith, C. D. et al. 2016. Refinements for embryo implantation surgery in the mouse: Comparison of injectable and inhalant anesthesias – tribromoethanol, ketamine and isoflurane – on pregnancy and pup survival. Laboratory Animals 50(5), 335-343.

An essential aspect of genetically-engineered mice (GEM) is the ability to produce live animals after the appropriate injection procedure. Animals are produced by implantation of manipulated embryos into pseudopregnant females for gestation, parturition, and growth...

Weaver, S. R., Cronick, C. M., Prichard, A. P. et al. 2016. Use of the RatLoft decreases pup mortality in lactating mice. Laboratory Animals 50(5), 370-378.

Lactating mice in laboratory conditions are thought to be under considerable stress. Dams may manifest this stress through a decrease in milk yield and/or increase in infanticide. The purpose of this study was to examine...

Valentim, A. M., Guedes, S. R., Pereira, A. M. et al. 2016. Euthanasia using gaseous agents in laboratory rodents. Laboratory Animals 50(4), 241-253.

Several questions have been raised in recent years about the euthanasia of laboratory rodents. Euthanasia using inhaled agents is considered to be a suitable aesthetic method for use with a large number of animals simultaneously...

Powell, K., Ethun, K., Taylor, D. K. 2016. The effect of light level, CO2 flow rate, and anesthesia on the stress response of mice during CO2 euthanasia. Lab Animal 45(10), 386-395.

Euthanasia protocols are designed to mitigate the stress experienced by animals, and an environment that induces minimal stress helps achieve that goal. A protocol that is efficient and practical in a typical animal research facility...

Mattheis, L., Jung, J.-S., Hiebl, B. et al. 2016. Perioperative support reduces mortality of obese BALB/c mice after ovariectomy. Lab Animal 45(7), 262-267.

The incidence of obesity is on the rise in most western countries and represents major risks to health. Obesity causes complex metabolic dysfunctions and can be associated with a large number of secondary diseases. To...

Hawkins, P., Prescott, M., Carbone, L. et al. 2016. A good death? Report of the second Newcastle meeting on laboratory animal euthanasia. Animals 6(9), 50.

Millions of laboratory animals are killed each year worldwide. There is an ethical, and in many countries also a legal, imperative to ensure those deaths cause minimal suffering. However, there is a lack of consensus...

Gardiner, P. 2016. Going outside ASPA guidelines. Animal Technology and Welfare 15(1), 47-52.

This article will discuss an improved and refined technique used for working and caring for a group of diabetic mice. As a team of animal technologists, academics and named veterinary surgeon, we developed a new...

Moody, C. M., Makowska, I. J., Weary, D. M. 2015. Testing three measures of mouse insensibility following induction with isoflurane or carbon dioxide gas for a more humane euthanasia. Applied Animal Behaviour Science 163, 183-87.

Laboratory mice are commonly killed via exposure to gradually increasing concentrations of isoflurane and carbon dioxide (CO2) gas. Once rendered insensible using isoflurane or CO2, a high concentration of CO2 is used to decrease time...

Jackson, E., Demarest, K., Eckert, W. J. et al. 2015. Aspen shaving versus chip bedding: Effects on breeding and behavior. Laboratory Animals 49(1), 46-56.

The choice of laboratory cage bedding material is often based on both practical and husbandry issues, whereas behavioral outcomes rarely appear to be considered. It has been noted that a breeding success difference appears to...

Lima, F. B., de Oliveira, E. S. 2014. What is the impact of low testosterone levels on the anatomical and behavioral repertoire of long-term enriched housing of male mice? Behavioral Processes 108, 57-64.

Environmental enrichment is a strategy to improve animal welfare, providing brain plasticity with changes at cellular, molecular and behavioral levels. In order to test the long-term effects of enriched housing and the importance of testosterone...