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. 
Khoo, S. Y.-S., Lay, B. P. P., Joya, J. et al. 2018. Local anaesthetic refinement of pentobarbital euthanasia reduces abdominal writhing without affecting immunohistochemical endpoints in rats. Laboratory Animals 52(2), 152-162.

Sodium pentobarbital is a commonly used agent for euthanizing laboratory rats, however its high pH can cause abdominal discomfort after intraperitoneal injection. Previous studies suggest that the addition of a local anaesthetic may alleviate this...

Grist, A., Lines, J., Knowles, T. et al. 2018. The use of a mechanical non-penetrating captive bolt device for the euthanasia of neonate lambs. Animals 8(4), 49.

A non-penetrating captive bolt device, powered by a 1-grain 0.22″ cartridge delivering a calculated kinetic energy of 47 Joules was tested as a euthanasia method on 200 neonate lambs (Ovis aries) of 4.464 kg (SD...

Mason, A., Tolo, E., Hektoen, L. et al. 2018. The effect of electrical head-to-chest stunning on the EEG in sheep. Animal Welfare 27(4), 343-350.

Head-to-body stunning is regarded as ‘best practice’ stunning for sheep. The benefits are loss of consciousness followed by cardiac arrest, death, prevention of animal movements post stun/kill and improved meat quality. Commercial equipment places electrodes...

Hocking, A. J., Elliot, D., Hua, J. et al. 2018. Administering fixed oral doses of curcumin to rats through voluntary consumption. JAALAS 57(5), 508–512.

Curcumin, a polyphenol derived from turmeric, has a wide variety of therapeutic benefits including antiinflammatory, antioxidative, and chemopreventative effects. Oral gavage is widely performed to administer curcumin in laboratory rodents in several experimental models. Although...

Hickman D. L. 2018. Interpreting neuroendocrine hormones, corticosterone, and blood glucose to assess the wellbeing of anesthetized rats during euthanasia. JAALAS 57(6), 725–728.

Current recommendations for assessing animal wellbeing during euthanasia suggest that measuring neuroendocrine hormones—such as ACTH, noradrenaline, and adrenaline—is preferable to measuring corticosterone and blood glucose because of the sensitivity of neuroendocrine hormones to the acute...

Hickman D. L. 2018. Home cage compared with induction chamber for euthanasia of laboratory rats. JAALAS 57(6), 729–733.

This study compared behavioral and physiologic changes in Sprague–Dawley and Brown Norway rats that were euthanized by using a 30% volume displacement rate of CO2 in either their home cage or an induction chamber; rats...

Raya, J., Neves Girardi , C. E., Hipólide, D. C. 2019. Corticosterone assimilation by a voluntary oral administration in palatable food to rats. Journal of Applied Animal Welfare Science 22(1), 37-41.

Drug delivery in research on nonhuman animals in the laboratory is still challenging because it is usually invasive and stressful. Stress-free voluntary oral drug administration in water lacks precise control of dose and timing of...

Edwards, G. L., Michael, J. A., Parks., A. 2018. Agricultural animals as biomedical models: Occupational health and safety considerations. ILAR Journal 59(2), 161-167.

The use of agricultural animals in biomedical research is increasing. Their overall size and metabolic rate, organ size, longer gestation period, and other physiological similarities make them good candidates for animal models of human disease...

Byrd, R., Boyd, S., Buckmaster, C. 2018. Rat thunder jacket— A zen experience. Laboratory Animal Science Professional 6(3) (September), 55-57.

Germ-free rats are fairly uncommon, relative to germ-free mice, and restraining these animals safely and effectively for compound administration and blood collection can be challenging. There are many commercially available varieties of restraint devices, but...

Walsh, J., Percival, A., Turner, P. 2017. Efficacy of blunt force trauma, a novel mechanical cervical dislocation device, and a non-penetrating captive bolt device for on-farm euthanasia of pre-weaned kits, growers, and adult commercial meat rabbits. Animals 7(12), 100.

The commercial meat rabbit industry is without validated on-farm euthanasia methods, potentially resulting in inadequate euthanasia protocols. We evaluated blunt force trauma (BFT), a mechanical cervical dislocation device (MCD), and a non-penetrating captive bolt device...

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...

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...

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...

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...

Schneider, B. M., Erhard, M. H., Scheipl, F. et al. 2016. Comparison of 2 gentling programs for laboratory rats: Effects on the behavior toward humans. Journal of Veterinary Behavior 12, 73-81.

Gentling can reduce the fear reactions of young laboratory rats toward people long term. We were able to show this outcome in a previous study that involved a successful but elaborate gentling program. In the...

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...

Reinhardt, V. (ed.) 2013. Compassion Makes a Difference - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume III. Animal Welfare Institute, Washington, DC.

This is the third volume of discussions that took place on the Laboratory Animal Refinement & Enrichment Forum (LAREF). This forum is dedicated to the exchange of personal experiences of refining the conditions under which...

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...

Cruden, J., Bester, J., Baines, N. et al. 2013. Will a more consistent handling method lead to a calmer rabbit? Animal Technology and Welfare 11, 127-130.

The authors describe various methods of handling and restraining rabbits, and propose that while many methods are appropriate, rabbits respond better if only one method is used consistently.

Cloutier, S., Baker, C., Wahl, K. et al. 2013. Playful handling as social enrichment for individually- and group-housed laboratory rats. Applied Animal Behaviour Science 143(2-4), 85-95.

Social housing is recommended for laboratory rats because they are highly social mammals but research constraints or medical issues often demand individual housing and, when social housing is practiced, it typically involves housing with only...

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...