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. 
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...

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...

Tuttle, A. H., Molinaro, M. J., Jethwa, J. F. et al. 2018. A deep neural network to assess spontaneous pain from mouse facial expressions. Molecular Pain 14, 1-9.

Grimace scales quantify characteristic facial expressions associated with spontaneous pain in rodents and other mammals. However, these scales have not been widely adopted largely because of the time and effort required for highly trained humans...

Clegg, I. 2018. Cognitive bias in zoo animals: An optimistic outlook for welfare assessment. Animals 8(7), 104.

Cognitive bias testing measures how emotional states can affect cognitive processes, often described using the “glass half-full/half-empty” paradigm. Classical or operant conditioning is used to measure responses to ambiguous cues, and it has been reported...

Wolfensohn, S., Shotton, J., Bowley, H. et al. 2018. Assessment of welfare in zoo animals: Towards optimum quality of life. Animals 8(7), 110.

Zoos are required to maintain a high standard of animal welfare, and this can be assessed using a combination of resource-based and animal-based indices usually divided into behavioural indicators, physiological indicators and clinical/pathological signs. Modern...

Oliver, V. L., Thurston, S. E., Lofgren, J. L. 2018. Using cageside measures to evaluate analgesic efficacy in mice (Mus musculus) after surgery. JAALAS 57(2), 186-201.

Recent studies have revealed some of the most frequently used analgesics in mice are not effectively treating postoperative pain. Our laboratory sought to compare and assess the validity and reliability of 2 cageside pain assessments...

Dudley, E. S., Boivin, G. P. 2018. Evaluation of a commercially available euthanasia solution as a voluntarily ingested euthanasia agent in laboratory mice. JAALAS 57(1), 30-34.

All currently accepted methods of euthanasia for laboratory mice involve some degree of stress, fear, anxiety, or pain. We evaluated the voluntary oral administration of a euthanasia drug in 99 male and 81 female mice...

Wallace, C. K., Bright, L. A., Marx, J. O. et al. 2018. Effectiveness of rapid cooling as a method of euthanasia for young zebrafish (Danio rerio). JAALAS 57(1), 58-63.

Despite increased use of zebrafish (Danio rerio) in biomedical research, consistent information regarding appropriate euthanasia methods, particularly for embryos, is sparse. Current literature indicates that rapid cooling is an effective method of euthanasia for adult...

Jones, S., Neville, V., Higgs, L. et al. 2018. Assessing animal affect: An automated and self-initiated judgement bias task based on natural investigative behaviour. Scientific Reports 8, 12400.

Scientific methods for assessing animal affect, especially affective valence (positivity or negativity), allow us to evaluate animal welfare and the effectiveness of 3Rs Refinements designed to improve wellbeing. Judgement bias tasks measure valence; however, task-training...

Mei, J., Riedel, N., Grittner, U. et al. 2018. Body temperature measurement in mice during acute illness: Implantable temperature transponder versus surface infrared thermometry. Scientific Reports 8, 3526.

Body temperature is a valuable parameter in determining the wellbeing of laboratory animals. However, using body temperature to refine humane endpoints during acute illness generally lacks comprehensiveness and exposes to inter-observer bias. Here we compared...

Sneddon, L. U., Lopez-Luna, J., Wolfenden, D. et al. 2018. Fish sentience denial: Muddying the waters. Animal Sentience 21(1).

Recent empirical studies have reported evidence that many aquatic species, including fish, cephalopods and crustaceans, have the capacity for nociception and pain, and that their welfare should be taken into consideration. Some sceptics, rejecting the...

Lahger, C., Laska, M. 2018. Behavioral responses of CD-1 mice to conspecific and heterospecific blood odors and to a blood odor component. Physiology & Behavior 184, 2015-210.

The odor of blood may have both aversive and attractive properties for mammals, depending on the species of the odor donor and the species perceiving the odor. To better understand the informational content of blood...

van Wijk, H., Crossman, L., Adjin-Tettey, G. et al. 2018. Advances in animal welfare and scientific outcomes of the bile duct cannulated rat model utilised in ADME studies. Animal Technology and Welfare 17(1), 64-67.

Since rats lack a gall bladder, they are an ideal model for investigating continuous biliary excretion and biotransformation. The design and implementation of a modified tail cuff and cannula system introduced at Covance permits the...

Creamer-Hente, M. A., Lao, F. K., Dragos, Z. P. et al. 2018. Sex- and strain-related differences in the stress response of mice to CO₂ euthanasia. JAALAS 57(5), 513–519.

The 2013 edition of the AVMA Guidelines for the Euthanasia of Animals recommends a 10% to 30% volume displacement rate (VDR) per minute for CO2 euthanasia of rodents. Here we sought to evaluate behavior and...

Fiebig, K., Jourdan, T., Kock, M. H. et al. 2018. Evaluation of infrared thermography for temperature measurement in adult male NMRI nude mice. JAALAS 57(6), 715–724.

Temperature monitoring during critical care provides important data required to guide treatment delivery. Body temperature is an easily quantified clinical parameter that can yield much information concerning the health of an animal. In research settings...

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...

Clark, T. S., Pandolfo, L. M., Marshall, C. M. et al. 2018. Body condition scoring for adult zebrafish (Danio rerio). JAALAS 57(6), 698–702.

Body condition scoring (BCS) is a simple, rapid, noninvasive tool used to assess body condition in animals. In this study, we developed and validated a diagram-based BCS for adult zebrafish (Danio rerio), a popular research...

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...

Häger, C., Keubler, L. M., Talbot, S. R. et al. 2018. Running in the wheel: Defining individual severity levels in mice. PLOS Biology 16(10), e2006159.

The fine-scale grading of the severity experienced by animals used in research constitutes a key element of the 3Rs (replace, reduce, and refine) principles and a legal requirement in the European Union Directive 2010/63/EU. Particularly...

Marquardt, N., Feja, M., Hünigen, H. et al. 2018. Euthanasia of laboratory mice: Are isoflurane and sevoflurane real alternatives to carbon dioxide? PLOS ONE 13(9), e0203793.

In the European Union (EU) millions of laboratory mice are used and killed for experimental and other scientific purposes each year. Although controversially discussed, the use of carbon dioxide (CO2) is still permitted for killing...

Norton, B. B., Tunseth, D., Holder, K. et al. 2018. Causes of morbidity in captive African lions (Panthera leo) in North America, 2001–2016. Zoo Biology 37(5), 354-359.

The lion (Panthera leo) is an iconic resident of zoos and wild animal parks throughout the world. Regular assessment of the morbidity of captive lions is necessary to address wellness concerns and improve the healthcare...

Köhler, A., Collymore, C., Finger-Baier, K. et al. 2017. Report of Workshop on Euthanasia for Zebrafish—A Matter of welfare and science. Zebrafish 14(6), 547-551.

The increasing importance of zebrafish as a biomedical model organism is reflected by the steadily growing number of publications and laboratories working with this species. Regulatory recommendations for euthanasia as issued in Directive 2010/63/EU are...

Lopez-Luna, J., Al-Jubouri, Q., Al-Nuaimy, W. et al. 2017. Reduction in activity by noxious chemical stimulation is ameliorated by immersion in analgesic drugs in zebrafish. Journal of Experimental Biology 220(8), 1451-1458.

Research has recently demonstrated that larval zebrafish show similar molecular responses to nociception to those of adults. Our study explored whether unprotected larval zebrafish exhibited altered behaviour after exposure to noxious chemicals and screened a...

White, L. J., Thomson, J. S., Pounder, K. C. et al. 2017. The impact of social context on behaviour and the recovery from welfare challenges in zebrafish, Danio rerio. Animal Behaviour 132, 189-199.

Understanding how animals experience stress in a laboratory environment is crucial for improving their welfare. Increasing numbers of fish are being used in scientific studies and further research is required to ensure appropriate conditions are...