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. 
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...

Hube, D., van Meegen, C., Herbrandt, S. et al. 2023. Hair corticosterone concentration as a potential stress marker in pet rabbits. Veterinary Record 193(9), e3464.

Background As a prey species, rabbits tend to hide their illnesses and injuries. Consequently, pet rabbit owners often do not notice that their pet may be suffering. Methods Data on the housing and health of...

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...

Neville, V., Lind, J., Mendl, E. et al. 2023. A mapping review of refinements to laboratory rat housing and husbandry. Lab Animal 52(3), 63–74.

Refining the housing and husbandry of laboratory rats is an important goal, both for ethical reasons and to allow better quality research. We conducted a mapping review of 1,017 studies investigating potential refinements of housing...

Wongsaengchan, C., McCafferty, D. J., Evans, N. P. et al. 2023. Body surface temperature of rats reveals both magnitude and sex differences in the acute stress response. Physiology & Behavior 264, 114138.

Understanding how biological markers of stress relate to stressor magnitude is much needed and can be used in welfare assessment. Changes in body surface temperature can be measured using infrared thermography (IRT) as a marker...

Ayala-Méndez, G. X., Calderón, V. M., Zuñiga-Pimentel, T. A. et al. 2023. Noninvasive monitoring of blood pressure and heart rate during estrous cycle phases in bormotensive Wistar–Kyoto and spontaneously hypertensive female rats. JAALAS 62(3), 267–273.

Since 2015, the National Institutes of Health has called for its funded preclinical research to include both male and female subjects. However, much of the basic animal research that has studied heart rate and blood...

Cho, E., Walsh, C. A., D’Angelo-Gavrish, N. M. et al. 2023. Effects of housing density on reproductive performance, intracage ammonia, and welfare of mice continuously housed as breeders in standard mouse and rat caging. JAALAS 62(2), 116–122.

Maintaining compliance with cage density recommendations in The Guide for the Care and Use of Laboratory Animals precludes continuous trio breeding in standard-sized mouse cages. This study evaluated and compared several parameters of reproductive performance...

Clancy, B. M., Theriault, B. R., Turcios, R. et al. 2023. The effect of noise, vibration, and light disturbances from daily health checks on breeding performance, nest building, and corticosterone in mice. JAALAS 62(4), 291–302.

At our institution, the techniques that technicians use for health checks vary for mice housed in cages on individually ventilated caging (IVC) racks. If the mice cannot be adequately visualized, some technicians partially undock the...

Gates, K. V., Alamaw, E., Jampachaisri, K. et al. 2023. Efficacy of supplemental diet gels for preventing postoperative weight loss in mice (Mus musculus). JAALAS 62(1), 87–91.

This study investigated whether the use of commercially available diet gels prevented the postoperative weight loss associated with major survival surgery in mice. C57BL/6 mice were divided into 3 groups (n = 9 per group)...

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...

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...

Blenkuš, U., Gerós, A. F., Carpinteiro, C. et al. 2022. Non-invasive assessment of mild stress-induced hyperthermia by infrared thermography in laboratory mice. Animals 12(2), 177.

Stress-induced hyperthermia (SIH) is a physiological response to acute stressors in mammals, shown as an increase in core body temperature, with redirection of blood flow from the periphery to vital organs. Typical temperature assessment methods...

Davis, H. J., Barabas, A. J., Gaskill, B. N. 2022. Titrating the preferences of altered lighting against temperature in female CD-1 laboratory mice, Mus musculus. Applied Animal Behaviour Science 246, 105541.

Aspects of the laboratory are aversive to mice, such as being housed under bright lights and at temperatures below their thermal comfort, causing stress and poor welfare. While murine thermal preferences are well understood, light...

Merley, A. L., Hubbard, J. S., Rendahl, A. K. et al. 2022. Behavioral and physiologic effects of dirty bedding exposure in female ICR mice. JAALAS 61(1), 42-51.

Exposure of sentinel mice to dirty bedding is commonly used in health monitoring programs to screen colonies for clinical and subclinical disease. Despite the potential stressors present in dirty bedding, including but not limited to...

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...

Buckmaster, C. L., Levesque, D., LaFollette, M. et al. 2022. Five hot topics in refinement of nonhuman primate neuroscience research. Laboratory Animal Science Professional 10(1) (January/February), 24-26.

Members of the North American 3Rs Collaborative (NA3RsC) refinement initiative have chosen to summarize developments in five hot topics of interest: 1. Tips for welfare-friendly transport, chairing, and restraint; 2. Guidance on refining food and...

Scorrano, F. 2022. A new feeder device to provide cleaner and accessible diet gel to laboratory mice. Laboratory Animal Science Professional 10(2) (March/April), 50-52.

Gel solutions are simple to use, have a relative long shelf life and can be delivered with plastic cups or pouches. A common issue encountered by many institutions is that the gel becomes soiled quickly...

Clay, A. W., Crane, M. M., Bloomsmith, M. A. 2022. Weight management towards physiological and behavioral wellbeing for chimpanzees living under human care. Zoo Biology 41(3), 200-217.

Across a period of 54 months, several changes were made to the feeding protocols of 32 adult chimpanzees living at the Yerkes National Primate Research Center Field Station. Before implementing any changes in diet, baseline...

Stevens, C., Dobbinson, K., Brook, E. et al. 2022. Report of the 2021 RSPCA/UFAW Rodent Welfare Group meeting. Animal Technology and Welfare 21(2), 83-91.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 28 years, so that its members can discuss current welfare research, exchange views on welfare issues and share experiences of...

Kolbe, T., Lassnig, C., Poelzl, A. et al. 2022. Effect of different ambient temperatures on reproductive outcome and stress level of lactating females in two mouse strains. Animals 12(16), 2141.

Ambient temperature is an important non-biotic environmental factor influencing immunological and oncological parameters in laboratory mice. It is under discussion which temperature is more appropriate and whether the commonly used room temperature in rodent facilities...

Berthel, R., Simmler, M., Dohme-Meier, F. et al. 2022. Dairy sheep and goats prefer the single components over the mixed ration. Frontiers in Veterinary Science 9, 1017669.

Mixed rations provide ruminants with a balanced diet by aiming to prevent selective feeding. However, this is a natural behavior of sheep and goats based on their dietary needs and the nutritional properties of feedstuffs...

Vogt, M. E., Riesgo, V. R., Flanigan, K. A. S. et al. 2022. Housing environment affects pubertal onset, anxiety-like behavior, and object interaction in male and female Long Evans rats. JAALAS 61(3), 241-247.

Rodents used for research can be humanely housed in a variety of ways. As such, a vast number of different housing environments are used, but are often not described in research publications. However, many elements...

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...