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. 
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...

Sutherland, M. A., Watson, T. J., Johnson, C. B. et al. 2016. Evaluation of the efficacy of a non-penetrating captive bolt to euthanase neonatal goats up to 48 hours of age. Animal Welfare 25(4), 471-479.

Manual blunt force trauma is a common method of euthanasia or culling of goat kids, however it is difficult to apply consistently and may vary in effectiveness. Therefore, a controlled mechanical method is needed. The...

Orford, F., Ford, E. A., Brown, S. N. et al. 2016. The evaluation of two commercial electric sheep stunning systems: current applied and the effect on heart function. Animal Welfare 25(3), 331-337.

The maintenance of head-only minimum stunning currents for sheep to ≥ 1.0 Amp as per current legislation was examined in two trials in a commercial abattoir. In the first trial, a Jetco MS100 stunner failed...

Gilliam, J. N., Shearer, J. K., Bahr, R. J. et al. 2016. Evaluation of brainstem disruption following penetrating captive-bolt shot in isolated cattle heads: comparison of traditional and alternative shot-placement landmarks. Animal Welfare 25(3), 347-353.

Currently recommended landmarks for captive-bolt euthanasia of cattle often result in failure to penetrate the brainstem. The purpose of this study was to evaluate the ability to disrupt the brainstem by placing the shot at...

Rodríguez, P., Dalmau, A., Manteca, X. et al. 2016. Assessment of aversion and unconsciousness during exposure to carbon dioxide at high concentration in lambs. Animal Welfare 25(1), 73-82.

The most widely used stunning method in sheep is electrical. However, in lambs, this method leads to rupture of the blood vessels, provoking ecchymoses. In pigs (Sus scrofa), the use of CO2-stunning systems has increased...

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...

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...

Hickman, D., Fitz, S., Bernabe, C. et al. 2016. Evaluation of low versus high volume per minute displacement CO2 methods of euthanasia in the induction and duration of panic-associated behavior and physiology. Animals 6(8), 45.

Current recommendations for the use of CO 2 as a euthanasia agent for rats require the use of gradual fill protocols (such as 10% to 30% volume displacement per minute) in order to render the...

Zatroch, K. K., Knight, C. G., Reime, J. N. et al. 2017. Refinement of intraperitoneal injection of sodium pentobarbital for euthanasia in laboratory rats (Rattus norvegicus). BMC Veterinary Research 13, 60.

Background: The Canadian Council on Animal Care and American Veterinary Medical Association classify intraperitoneal (IP) pentobarbital as an acceptable euthanasia method in rats. However, national guidelines do not exist for a recommended dose or volume...

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...

Boulanger Bertolus, J., Nemeth, G., Makowska, I. J. et al. 2015. Rat aversion to sevoflurane and isoflurane. Applied Animal Behaviour Science 164, 73-80.

Virtually all rodents used in research are eventually euthanized. Best practice is to anaesthetize these animals before euthanasia using a halogenated anaesthetic such as isoflurane. Exposure to isoflurane is aversive, but less so than exposure...

Pearson, B. L., Reeder, D. M., Judge, P. G. 2015. Crowding increases salivary cortisol but not self-directed behavior in captive baboons. American Journal of Primatology 77, 462-67.

Reduced space can lead to crowding in social animals. Crowding increases the risk of agonistic interactions that, in turn, may require additional physiological defensive coping mechanisms affecting health. To determine the stress induced from increased...

Bode, A. E., Barber, H. 2014. Use of vinyl nonadhesive tape as an alternative for positioning rodents in small animal imaging. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 597-598. (Abstract #P185).

Specific positioning for different imaging modalities is essential in our small animal imaging core. While we have different animal holders designed to position the animal inside the MRI, additional securing of the animal to the...

Lambeth, S. P., Schapiro, S. J., Bernacky, B. J. et al. 2013. Establishing 'quality of life' parameters using behavioural guidelines for humane euthanasia of captive non-human primates. Animal Welfare 22(4) 429-435.

Chronic pain and distress are universally accepted conditions that may adversely affect an animal’s quality of life (QOL) and lead to the humane euthanasia of an animal. At most research institutions and zoological parks in...

Wong, D., Makowska, I. J., Weary, D. M. 2013. Rat aversion to isoflurane versus carbon dioxide. Biology Letters 9(1), 20121000.

Some experts suggest that sedation of laboratory rodents with isoflurane before euthanasia with carbon dioxide (CO2) is a humane alternative to euthanasia with CO2 alone, but little research has compared aversion with these agents. Albino...

Chisholm, J., De Rantere D., Fernandez, N. J. et al. 2013. Carbon dioxide, but not isoflurane, elicits ultrasonic vocalizations in female rats. Laboratory Animals 47(4), 324-7.

Gradual filling of a chamber with carbon dioxide is currently listed by the Canadian Council on Animal Care guidelines as a conditionally acceptable method of euthanasia for rats. Behavioural evidence suggests, however, that exposure to...

Whittaker, A. L., Howarth, G. S., Hickman, D. L. 2012. Effects of space allocation and housing density on measures of wellbeing in laboratory mice: A review. Laboratory Animals 46(1), 3-13.

In the majority of countries where there are legislative requirements pertaining to the use of animals in research, figures are quoted for minimum cage sizes or space allocation to be provided per animal. These figures...

Howard, B., Nevalainen, T., Perretta, G. (ed). 2010. The COST Manual of Laboratory Animal Care and Use: Refinement, Reduction, and Research (1st Ed). CRC Press, Boca Raton, FL.

COST Action B-24 established four working groups to research and discuss issues relevant to laboratory animal science. These included the housing of animals, environmental needs, refinement of procedures, genetically modified animals, and cost-benefit analysis. Based...

Reed, B., Hawkins, P., Latham, N. et al. 2008. Report of the 2006 RSPCA/UFAW Rodent Welfare Group meeting. Lab Animal 37(5), 216-222.

The RSPCA/UFAW Rodent Welfare Group holds a one-day meeting every autumn to discuss current welfare research and to exchange views on rodent welfare issues. A key aim of the group is to encourage people to...

Onbasilar, E. E., Onbasilar, Í. 2007. Effect of cage density and sex on growth, food utilization and some stress parameters of young rabbits. Scandinavian Journal of Laboratory Animal Science 34(3),189-195.

The aim of the experiment was to study the effects of cage density (1, 3 and 5 rabbits per cage) and sex (male and female) on stress parameters of young rabbits. A total of 90...

Conour, L. A., Murray, K. A., Brown, M. J. 2006. Preparation of animals for research -- Issues to consider for rodents and rabbits. ILAR Journal 47(4), 283-293.

This article provides details to consider when preparing to use animals in biomedical research. The stress of transport and receipt of animals into a new environment mandate the need for a period of stabilization and...

Smith, A. L., Mabus, S. L., Muir, C. et al. 2005. Effects of housing density and cage floor space on three strains of young adult inbred mice. Comparative Medicine 55(4), 368-376.

Some recommendations in the Guide for the Care and Use of Laboratory Animals (the Guide) are based on best professional judgment. Our current efforts are directed toward replacement with data-driven standards. We demonstrated earlier that...

Sharp, J. L., Zammit, T., Azar, T. A. et al. 2003. Are "by-stander" female Sprague-Dawley rats affected by experimental procedures? Contemporary Topics in Laboratory Animal Science 42(1), 19-28.

The objective of this study was to test the hypotheses that female rats are stressed by being in the same room as animals subjected to common husbandry and experimental procedures and that the level of...