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. 
Jensen, V. F. H., Mølck, A.-M., Martensson, M. et al. 2017. Assessment of implantable infusion pumps for continuous infusion of human insulin in rats: Potential for group housing. Laboratory Animals 51(3), 273-283.

Group housing is considered to be important for rats, which are highly sociable animals. Single housing may impact behaviour and levels of circulating stress hormones. Rats are typically used in the toxicological evaluation of insulin...

Miranda, A., Pego, J. M., Correia-Pinto, J. 2017. Animal facility videoendoscopic intubation station: Tips and tricks from mice to rabbits. Laboratory Animals 51(2), 204-207.

Endotracheal intubation of laboratory animals is a common procedure shared by several research fields for different purposes, such as mechanical ventilation of anaesthetized animals, instillation of cytotoxic nanoparticles, infectious agents or tumour cells for induction...

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...

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...

Carter, C. L, Adams, J. K., Czarra, J. A. et al. 2016. An incidence of pseudopregnancy associated with the social enrichment of rabbits (Oryctolagus cuniculi). JAALAS 55(1), 98-99.

Here we describe a case of pseudopregnancy in a New Zealand White rabbit as a result of pair housing with an aggressive conspecific. Clinical signs included fur pulling and nest building that developed shortly after...

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...

Kruger, M. C., Morel, P. C. H. 2016. Experimental control for the ovariectomized rat model: Use of sham versus nonmanipulated animal. Journal of Applied Animal Welfare Science 19(1), 73-80.

One of 2 models required by the U.S. Food and Drug Administration for registration of a treatment for osteoporosis, the ovariectomized (OVX) rat model, is widely used in scientific studies investigating sex hormone-deficient bone loss...

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...

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...

Gaskill, B. N., Pritchett-Corning, K. R. 2015. Effect of cage space on behavior and reproduction in CRl:CD(SD) and BN/Crl laboratory rats. JAALAS 54(5), 497-506.

The 2011 Guide for the Care and Use of Laboratory Animals contains recommendations regarding the amount of cage space for mothers with litters. Literature on cage-space use in breeding rats is sparse. We hypothesized that...

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...

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...

Braden, G.C., Rasmussen, S., Tolwani, R.J. 2014. Effects of breeding configuration on behavior, reproduction, and pathology in the laboratory mouse (Mus musculus). American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 605. (Abstract #P210).

While numerous published studies have evaluated the effect of housing density on the wellbeing of laboratory mice, little is known on the effect of breeding configuration. The eighth edition of the Guide for the Care...

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...