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. 
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...

Lehmann, H., Blache, D., Drynan, E. et al. 2017. Optimum drug combinations for the sedation of growing boars prior to castration. Animals 7(8), 61.

Juvenile male pigs were sedated for castration. Eight five-month old boars were sedated twice (two weeks apart) with a combination of detomidine (0.1 mg/kg), midazolam (0.2 mg/kg) and either butorphanol (0.2 mg/kg) (Group MDB, n...

Vermeer, H., Dirx-Kuijken, N., Bracke, M. 2017. Exploration feeding and higher space allocation improve welfare of growing-finishing pigs. Animals 7(5), 36.

Lack of environmental enrichment and high stocking densities in growing-finishing pigs can lead to adverse social behaviors directed to pen mates, resulting in skin lesions, lameness, and tail biting. The objective of the study was...

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...

Barker, T. H., Bobrovskaya, L., Howarth, G. S. et al. 2017. Female rats display fewer optimistic responses in a judgment bias test in the absence of a physiological stress response. Physiology & Behavior 173, 124-131.

Metabolic cages are a type of housing used in biomedical research. Metabolic cage housing has been demonstrated to elicit behavioural and physiological changes in rodents housed within them. The nature of this effect has been...

Kleefeld, S., Bannerton, K., Kelly, J.2017. Effect of moderate environmental enrichment on commonly used behavioural tests in rats. Animal Technology and Welfare 16(1), 75-76.

The environment that laboratory animals are housed in should reflect their natural habitats in a manner that can satisfy their innate physiological and behavioural needs. This includes nest building, hiding, exploring and foraging. Providing environmental...

Davis, K., Seddon, Y., Creutzinger, K. et al. 2017. An investigation into the use of sucrose to reduce castration pain in piglets. Canadian Journal of Animal Science 97(3), 439-447.

Oral sucrose was evaluated for its ability to reduce pain following castration. Piglets (n = 126) were assigned to one of the five treatments: (1) castrated and given 3 mL of water (C); (2) castrated...

Stracke, J., Otten, W., Tuchscherer, A. et al. 2017. Dietary tryptophan supplementation and affective state in pigs. Journal of Veterinary Behavior 20, 82-90.

The assessment and provision of welfare in farm animals has become a major issue in animal science. A key element for providing good welfare is the enabling of positive affective states in the animals. As...

Makowska, I. J., Weary, D. M. 2016. Differences in anticipatory behaviour between rats (Rattus norvegicus) housed in standard versus semi-naturalistic laboratory environments. PLOS ONE 11(1), e0147595.

Laboratory rats are usually kept in relatively small cages, but research has shown that they prefer larger and more complex environments. The physiological, neurological and health effects of standard laboratory housing are well established, but...

Fiedler, K. J., Parsons, R. L., Sadler, L. J. et al. 2016. Effects of stocking rate on measures of efficacy and welfare during argon gas euthanasia of weaned pigs. Animal Welfare 25(1), 83-89.

The objective of this study was to evaluate the effects of chamber stocking rate on facets of animal welfare and efficacy during euthanasia of weaned pigs (Sus scrofa domesticus) with argon gas. Two hundred and...

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...

Christensen, J. W. 2016. Early-life object exposure with a habituated mother reduces fear reactions in foals. Animal Cognition 19(1), 171–179.

Fear reactions in horses are a major cause of horse–human accidents, and identification of effective pathways for reduction in fearfulness can help decreasing the frequency of accidents. For a young mammal, the mother is one...

Goumon, S., Špinka, M. 2016. Emotional contagion of distress in young pigs is potentiated by previous exposure to the same stressor. Animal Cognition 19(3), 501–511.

This study tested whether emotional contagion occurs when piglets directly observe a penmate in distress (restraint) and whether there is an effect of previous experience on the response to subsequent restraint or exposure to conspecific...

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...

Heyse, N. C., Brenes, J. C., Schwarting, R. K. W. 2015. Exercise reward induces appetitive 50-kHz calls in rats. Physiology & Behavior 147, 131-140.

Rats express affective states by visible behaviors (like approach or flight) and through different kinds of ultrasonic vocalizations (USV). 50-kHz calls are thought to reflect positive affective states since they occur during rewarding situations like...

Reimert, I., Bolhuis, J. E., Kemp, B. et al. 2015. Emotions on the loose: Emotional contagion and the role of oxytocin in pigs. Animal Cognition 18(2), 517–532.

We studied emotional contagion, a simple form of empathy, and the role of oxytocin herein in pigs. Two training pigs per pen (n = 16 pens) were subjected to a positive treatment (pairwise access to...

Murphy, E., Nordquist, R. E., van der Staay, F. J. 2014. A review of behavioural methods to study emotion and mood in pigs (Sus scrofa). Applied Animal Behaviour Science 159, 9-28.

The study of emotions in animals is of increasing importance to a number of disciplines such as animal welfare science and affective neuroscience. Pigs are a common farm animal species, most often reared in intensive...

Bartal, I. B.-A., Rodgers, D. A., Sarria, M. S. et al. 2014. Pro-social behavior in rats is modulated by social experience. eLife 3, e01385.

In mammals, helping is preferentially provided to members of one’s own group. Yet, it remains unclear how social experience shapes pro-social motivation. We found that rats helped trapped strangers by releasing them from a restrainer...

Jones, C. E., Riha, P. D., Gore, A. C. et al. 2014. Social transmission of Pavlovian fear: Fear-conditioning by-proxy in related female rats. Animal Cognition 17(3), 827–834.

Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a foot-shock) leads to associative learning such that the tone alone will elicit a conditioned response (e.g., freezing)...

Makowska, I. J., Weary, D. M. 2013. Assessing the emotions of laboratory rats. Applied Animal Behaviour Science 148, 1-12.

Rats are one of the most commonly used species in research, and decades of testing have yielded a large amount of information pertaining to their experience of emotion. The aim of this review is to...

Hrapkiewicz, K., Colby, L. A., Denison, P. 2013. Clinical Laboratory Animal Medicine: An Introduction (4th Ed). Wiley-Blackwell, Ames, IA.

Clinical Laboratory Animal Medicine: An Introduction, Fourth Edition offers a user-friendly guide to the unique anatomy and physiology, care, common diseases, and treatment of small mammals and nonhuman primates. Carefully designed for ease of use...

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...