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. 
Stevens, C., Hammonds, T., Hinchcliffe, J. et al. 2023. Report of the 2022 RSPCA/UFAW Rodent Welfare Group Meeting. Animal Technology and Welfare 22(2), 91–100.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 29 years, so that its members can discuss current welfare research, exchange views on welfare issues and share experiences of...

Gardhouse, S., Beaufrere, H., Hawkins, M. G. et al. 2023. Evaluation of oral transmucosal administration of pentobarbital for euthanasia of conscious wild birds. Journal of Applied Animal Welfare Science 26(1), 4–14.

This prospective study evaluated oral transmucosal pentobarbital sodium at three doses in 110 wild-caught wild birds requiring euthanasia. Birds received transmucosal pentobarbital at five (430 mg/kg), six (516 mg/kg), and seven times (602 mg/kg) the...

Munro, B. A., Merenick, D. R., Gee, J. M. et al. 2023. Use of loss of righting reflex to assess susceptibility to carbon dioxide gas in three mouse strains. JAALAS 62(6), 553–558.

Exposure to CO2 gas is a common rodent euthanasia method. CO2 activates nociceptors in rats and is painful to humans at concentrations equal to or greater than 32.5% The concentration of CO2 at which rodents...

Hickman, D. L. 2023. Euthanasia of neonatal rats and mice using carbon monoxide. JAALAS 62(3), 274–278.

Minimization of potential pain and distress of rodents undergoing euthanasia is a touchstone of veterinary clinical medicine. Evaluation of this issue in postweanling rodents has supported revisions to the AVMA (American Veterinary Medical Association) Guidelines...

McNamara, A., Ballantine, A. R., Deuchande, R. et al. 2023. Comparison of fixed and rising displacement rates of CO2 for euthanasia of aged rats. JAALAS 62(5), 453–463.

This study compared euthanasia induced by rising concentrations of CO2 in aged rats (n = 59) using different gas displacement rates. Rats were preimplanted with cardiovascular telemetry devices and had been previously used for short...

Olagbaju, T. T., Troan, B. V., Balko, J. A. 2023. Investigation of potassium chloride for euthanasia of anesthetized African clawed frogs (Xenopus laevis). JAALAS 62(4), 362–369.

Euthanasia is frequently performed in amphibians, but techniques are currently limited in number and variable in effectiveness. The current study examined the use of potassium chloride (KCl) for euthanasia of anesthetized African clawed frogs (Xenopus...

Stuckey, J. E., Makhija, S. D., Reimer, D. C. et al. 2023. Effects of different grades of carbon dioxide on euthanasia of mice (Mus musculus). JAALAS 62(5), 430–437.

Carbon dioxide (CO2) is a conditionally acceptable method for mouse euthanasia, according to the American Veterinary Medical Association Guidelines for the Euthanasia of Animals. In a 2012 Office of Laboratory Animal Welfare (OLAW) webinar, representatives...

Yoshida, K. 2023. Comparison of low and high doses of pentobarbital or thiopental for euthanasia of isoflurane-anesthetized pigs. JAALAS 62(2), 185–188.

Barbiturate overdose is a common method for euthanizing pigs. However, barbiturates can cause tissue damage and may affect experimental results, so the minimal dose should be used. The minimal dose of barbiturate for euthanasia in...

Kieffer, J. D., Campler, M. R., Cheng, T.-Y. et al. 2022. Evaluation of a water-based medium-expansion foam depopulation method in suckling and finisher pigs. Animals 12(8), 1041.

The threat of foreign animal disease introduction through contaminated animal products, feed ingredients, and wildlife vectors have highlighted the need for additional approved methods for mass depopulation of swine under emergency scenarios, especially methods that...

Hickman, D. L. 2022. Evaluation of carbon dioxide euthanasia of female Sprague Dawley rats alone or with unfamiliar conspecifics. JAALAS 61(2), 195-200.

Most studies evaluating methods of euthanasia to date have focused on the euthanasia of individual animals. However, larger chambers are commonly used to euthanize multiple cages of animals at once. This study evaluated the use...

Perret-Thiry, C., Raulic, J., Vergneau-Grosset, C. 2022. Evaluation of prolonged immersion in tricaine methanesulfonate for juvenile goldfish (Carassius auratus) euthanasia. Journal of the American Veterinary Medical Association 260(8), 911-915.

OBJECTIVE: Doses of buffered tricaine methanesulfonate (MS-222) up to 1000 mg/L for 15 minutes are reported inefficient to produce euthanasia in goldfish. The goal of this study was to determine if goldfish can be euthanized...

Guerrero-Martin, S. M., Brill, S., Carlson, B. W. 2022. Development and implementation of a positive reinforcement training program for nonhuman primates in biomedical research. Laboratory Animal Science Professional 10(1) (January/February), 48-52.

Despite clear benefits of PRT for NHPs and biomedical research, investigators often view the investment in personnel expertise and time required to train animals as deterrents towards adopting PRT. We provide an example of how...

Torcivia, C., McDonnell, S. 2022. Efficacy of lidocaine topical solution in reducing discomfort reaction of horses to intramuscular vaccination. Animals 12(13), 1659.

Vaccinations via intramuscular injection are a key component of preventative health care in horses. Development of problematic behavioral aversion to injections is quite common. Our clinical impression has been that topical anesthetic applied to injection...

Davis, A. K., Garner, J. P., Chu, D. K. et al. 2022. Propofol immersion as a euthanasia method for adult zebrafish (Danio rerio). Comparative Medicine 72(3), 204-209.

The exponential rise of the zebrafish (Danio rerio) as a model organism in biomedical research has far outstripped our un- derstanding of basic husbandry and welfare for this species. As a case in point, here...

Hickman, D. L. 2022. Minimal exposure times for irreversible euthanasia with carbon dioxide in mice and rats. JAALAS 61(3), 283-286.

When using an anesthetic overdose to euthanize laboratory rodents, a secondary method of euthanasia is recommended to ensure that the apparent death is irreversible. This secondary method usually is accomplished through the collection of tissues...

McKinney, M. M., Dupont, W. D., Corson, K. J. et al. 2022. Physiologic and behavioral effects in mice anesthetized with isoflurane in a red-tinted or a traditional translucent chamber. JAALAS 61(4), 322-332.

Isoflurane has been characterized as a distressing agent for rodents, causing both physiologic and behavioral effects. Using a "darkened home cage" has been recommended during CO2 administration for rodent euthanasia; this is arguably a similar...

Clarkson, J. M., Martin, J. E., McKeegan, D. E. F. 2022. A review of methods used to kill laboratory rodents: Issues and opportunities. Laboratory Animals 56(5), 419-436.

Rodents are the most widely used species for scientific purposes. A critical pre-requisite of their use, based on utilitarian ethical reasoning, is the provision of a humane death when necessary for scientific or welfare grounds...

Neil, D. M., Albalat, A., Thompson, J. 2022. The effects of electrical stunning on the nervous activity and physiological stress response of a commercially important decapod crustacean, the brown crab Cancer pagurus L. PLOS ONE 17(7), e0270960.

Increasing attention is being paid to the welfare of decapod crustaceans. Legislation exists for their humane slaughter in several countries and this is being debated in others. Electrical stunning may have potential for humane slaughter...

Tetlow, S. A. J., Brennan, M. L., Garcia-Ara, A. 2022. Welfare indicators for stunning versus non-stunning slaughter in sheep and cattle: A scoping review. Vet Record 191(6), e1739.

Background: While most cattle and sheep in the United Kingdom are stunned before slaughter, non-stun methods are permitted to supply meat to specific consumers. This study aimed to identify the existing literature that compared animal...

Ferreira, J. M., Félix, L., Jorge, S. et al. 2022. Anesthesia overdose versus rapid cooling for euthanasia of adult zebrafish. Zebrafish 19(4), 148-159.

The rapid increase in zebrafish use needs to be accompanied by research into the refinement of procedures. The European (EU) Directive lists three possible euthanasia methods for fish: anesthetic overdose, electrical stunning, and concussion. However...

Korenyi-Both, J., Vidaurre, J., Held, T. et al. 2022. Description of electroencephalographic data gathered using water-based medium-expansion foam as a depopulation method for nursery pigs. Scientific Reports 12(1), 16798.

The United States’ swine industry is under constant threat of foreign animal diseases, which may emerge without warning due to the globalized transportation networks moving people, animals, and products. Therefore, having disease control and elimination...

Korenyi-Both, J., Vidaurre, J., Held, T. et al. 2022. Description of electroencephalographic data gathered using water-based medium-expansion foam as a depopulation method for nursery pigs. Scientific Reports 12(1), 16798.

The United States’ swine industry is under constant threat of foreign animal diseases, which may emerge without warning due to the globalized transportation networks moving people, animals, and products. Therefore, having disease control and elimination...

Li, W., Yan, C., Descovich, K. et al. 2022. The effects of preslaughter electrical stunning on serum cortisol and meat quality parameters of a slow-growing Chinese chicken breed. Animals 12(20), 2866.

Electrical stunning is widely utilized prior to a neck cut to induce unconsciousness in order to improve animal welfare and slaughter efficiency in the broiler production industry. However, slaughter without stunning is still very commonly...

Martin, J. E., Baxter, E. M., Clarkson, J. M. et al. 2022. Characterizing candidate decompression rates for hypobaric hypoxic stunning of pigs. Part 1: Reflexive behavior and physiological responses. Frontiers in Veterinary Science 9, 1027878.

Alternatives to carbon dioxide (CO2) stunning for the commercial slaughter of pigs are urgently needed because there is robust evidence that exposing pigs to hypercapnic environments is associated with pain, fear, and distress. Hypobaric hypoxia...

Nuber, M., Gonzalez-Uarquin, F., Neufurth, M. et al. 2022. Development of a 3D simulator for training the mouse in utero electroporation. PLOS ONE 17(12), e0279004.

In utero electroporation (IUE) requires high-level training in microinjection through the mouse uterine wall into the lateral ventricle of the mouse brain. Training for IUE is currently being performed in live mice as no artificial...