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. 
Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...

Shomer, N. H., Allen-Worthington, K. H., Hickman, D. L. et al. 2020. Review of rodent euthanasia methods. JAALAS 59(3), 242–253.

The optimal choice of euthanasia method for laboratory rodents depends on a number of factors, including the scientific goals of the study, the need to minimize animal pain and/or distress, applicable guidelines and laws, the...

Laferriere, C. A., Pang, D. S. 2020. Review of intraperitoneal injection of sodium pentobarbital as a method of euthanasia in laboratory rodents. JAALAS 59(3), 254–263.

Euthanasia is one of the most commonly performed procedures in biomedical research, involving tens of millions of animals in North America and Europe every year. The use of sodium pentobarbital, injected intraperitoneally, for killing rodents...

Galex, I. A., Gallant, C. M., D'Avignon, N. et al. 2020. Evaluation of effective and practical euthanasia methods for larval African clawed frogs (Xenopus laevis). JAALAS 59(3), 269–274.

Larval, or tadpole-stage Xenopus laevis frogs are a popular research model for developmental biology and disease studies. Existing euthanasia guidance documents offer recommendations for both eggs and adult stages, yet do not specifically address the...

Cohen, S., Kwok, M., Huang, J. 2020. Humane euthanasia of guinea pigs (Cavia porcellus) with a penetrating spring-loaded captive bolt. Animals 10(8), 1356.

Guinea pigs (Cavia porcellus) have been used in research since the 19th century to collect data due to their physiological similarities to humans. Today, animals perform a vital role in experiments and concerns for laboratory...

Kulkarni, S., Hickman, D. 2020. Isoflurane and carbon dioxide elicit similar behavioral responses in rats. Animals 10(8), 1431.

Euthanasia in rodents is an ongoing topic of debate due to concerns regarding the aversive nature of gases with anesthetic properties such as carbon dioxide (CO2) and isoflurane. The aim of this study was to...

McMahon, S. A., Wigham, E. 2020. ‘All Ears’: A questionnaire of 1516 owner perceptions of the mental abilities of pet rabbits, subsequent resource provision, and the effect on welfare. Animals 10(10), 1730.

Pet rabbit welfare is a hidden crisis: Inappropriately housed, fed, and not routinely provided healthcare—rabbits can often suffer painful conditions and shortened lifespans. This study provides novel understanding of owners’ perceptions of rabbits’ mental capabilities...

Fife-Cook, I., Franks, B. 2019. Positive welfare for fishes: Rationale and areas for future study. Fishes 4(2), 31.

Traditional animal welfare paradigms have focused on maintaining physical health and mitigating negative impacts to wellbeing. Recently, however, the field has increasingly recognized the importance of positive welfare (i.e., mental and physical states that exceed...

Axiak Flammer, S., Eskes, C., Kohler, I. et al. 2019. Alternatives to carbon dioxide—Taking responsibility for humanely ending the life of animals. Animals 9(8), 482.

Carbon dioxide (CO2) is commonly used to kill rodents. However, a large body of research has now established that CO2 is aversive to them. A multidisciplinary symposium organized by the Swiss Federal Food Safety and...

Steiner, A. R., Axiak Flammer, S., Beausoleil, N. J. et al. 2019. Humanely ending the life of animals: Research priorities to identify alternatives to carbon dioxide. Animals 9(11), 911.

The use of carbon dioxide (CO2) for stunning and killing animals is considered to compromise welfare due to air hunger, anxiety, fear, and pain. Despite decades of research, no alternatives have so far been found...

LaFollette, M. R., Swan, M. P., Smith, R. K. et al. 2019. The effects of cage color and light intensity on rat affect during heterospecific play. Applied Animal Behaviour Science 219, 104834.

Environmental enrichment provides physiological and emotional benefits to laboratory rodents. Red tinted shelters are a common enrichment found in laboratories that provide rodents with a hiding space shielded from bright light. Red tinting alters the...

Williams, E., Carter, A., Hall, C. et al. 2019. Exploring the relationship between personality and social interactions in zoo-housed elephants: Incorporation of keeper expertise. Applied Animal Behaviour Science 221, 104876.

Individual animal personalities affect experiences of zoo environments, and thus potentially welfare. Incorporating keeper knowledge of animal personality in a reliable way has great value in optimising welfare in zoo-housed animals. Assessment of animal personality...

Stevens, C., Hawkins, P., Lovell-Badge, R. et al. 2019. Report of the 2018 RSPCA/UFAW Rodent and Rabbit Welfare Group meeting. Animal Technology and Welfare 18(2), 81-91.

The RSPCA/UFAW Rodent (and now Rabbit) Working Group has held a one-day meeting every autumn for the last 25 years, so that its members can discuss current welfare research, exchange views on welfare issues and...

Brudzynski, S. M. 2019. Emission of 22 kHz vocalizations in rats as an evolutionary equivalent of human crying: Relationship to depression. Behavioural Brain Research 363, 1-12.

There is no clear relationship between crying and depression based on human neuropsychiatric observations. This situation originates from lack of suitable animal models of human crying. In the present article, an attempt will be made...

Anders, N., Roth, B., Grimsbø, E. et al. 2019. Assessing the effectiveness of an electrical stunning and chilling protocol for the slaughter of Atlantic mackerel (Scomber scombrus). PLOS ONE 14(9), e0222122.

Inducing unconsciousness in fish using electrical stunning prior to slaughter may improve fish welfare and fillet quality if such practises can be disseminated into wild capture fisheries. The objectives of this study were to: 1)...

Améndola, L., Ratuski, A., Weary, D. M. 2019. Variation in the onset of CO2-induced anxiety in female Sprague Dawley rats. Scientific Reports 9, 19007.

Carbon dioxide (CO2) is commonly used to kill laboratory rats. Rats find CO2 aversive and aversion varies between individuals, indicating that rats vary in CO2 sensitivity. Healthy humans experience feelings of anxiety at concentrations similar...

Jirkof, P., Rudeck, J., Lewejohann, L. 2019. Assessing affective state in laboratory rodents to promote animal welfare—What is the progress in applied refinement research? Animals 9(12), 1026.

In the past, there was a strong focus on avoiding or reducing negative animal welfare in animal experimentation. Recently, the importance of promoting positive animal welfare in laboratory animals has been highlighted. To ensure and...

McMillan, F. D. (ed). 2019. Mental Health and Well-being in Animals (2nd ed). CABI, Wallingford, UK.

This second edition is fully revised, expanded, and comprehensively updated with the most current knowledge about the full array of mental health issues seen in animals. Written by key opinion leaders, internationally-recognized experts and specialists...

Kells, N. J., Beausoleil, N. J., Sutherland, M. A. et al. 2018. Electroencephalographic responses of anaesthetised rats to carbon dioxide inhalation. Animal Welfare 27(3), 215-223.

Exposure to high concentrations of CO2 is a common means of stunning and killing laboratory rodents. However, there is concern regarding the potential for animals to have aversive experiences, such as pain or breathlessness, prior...

Golledge, H., Carter, E. 2018. Welfare of fish farmed in the EU during transport and at slaughter. Animal Welfare 27(3), 287-288.

This Report, commissioned by the European Commission, summarises the current state of transport and slaughter practices in the aquaculture industry within eleven case-study countries in the European Economic Area (EAA). Comparisons are also made with...

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...

Balko, J. A., Oda, A., Posner, L. P. 2018. Use of tricaine methanesulfonate or propofol for immersion euthanasia of goldfish (Carassius auratus). Journal of the American Veterinary Medical Association 252(12), 1555-1561.

OBJECTIVE To substantiate current AVMA guidelines for immersion euthanasia of goldfish (Carassius auratus) with tricaine methanesulfonate (TMS), determine whether immersion in propofol at 5 times its immersion anesthesia concentration for 30 minutes is sufficient for...

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...