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...

Stevens, C., Finnegan, E., Clarkson, J. et al. 2020. Report of the 2019 RSPCA/UFAW Rodent Welfare meeting. Animal Technology and Welfare 19(2), 101-111.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 26 years, so that its members can discuss current welfare research, exchange views on welfare issues, and share experiences of...

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...

Laferriere, C. A., Leung, V. S., Pang, D. S. 2020. Evaluating intrahepatic and intraperitoneal sodium pentobarbital or ethanol for mouse euthanasia. JAALAS 59(3), 264–268.

Intraperitoneal (IP) injection of sodium pentobarbital (PB) is an accepted method of euthanasia for mice. However, this method has important drawbacks, including the potential for pain or misinjection. The objective of this prospective, randomized, blinded...

Baskir, E. A., Kucharski, S., Powell, D. M. 2020. Chinchilla (Chinchilla lanigera) behavioral responses to a visual signal preceding handling. Zoo Biology 39(6), 391-396.

Zoos use ambassador animals in educational programs featuring close contact with humans. Chinchillas (Chinchilla lanigera) at the Saint Louis Zoo are retrieved for programs by a keeper wearing brown handling gloves, but green cleaning gloves...

Dorey, N. R., Blandina, A., Udell, M. A. R. 2020. Clicker training does not enhance learning in mixed-breed shelter puppies (Canis familiaris). Journal of Veterinary Behavior 39, 57-63.

Clicker training has been a popular form of training for decades and is used in zoos, aquariums, and shelters. Only a handful of studies have investigated the efficacy of the clicker-training method itself despite its...

Vieira de Castro, A. C., Fuchs, D., Morello, G. M. et al. 2020. Does training method matter? Evidence for the negative impact of aversive-based methods on companion dog welfare. PLOS ONE 15(12), e0225023.

Dog training methods range broadly from those using mostly positive punishment and negative reinforcement (aversive-based) to those using primarily positive reinforcement (reward-based). Although aversive-based training has been strongly criticized for negatively affecting dog welfare, there...

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...

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...

Taniuchi, T., Ohgi, A., Nishikawa, M. 2019. Returning to home cage serves as an effective reward for maze learning in rats. Behavioural Processes 164, 175-177.

This study examined the effectiveness in rats of ‘returning to home cage’ as a reward for learning a Lashley III maze. Rats could return to their home cage directly (Direct HC group) or they could...

Dutton III, J. W., Artwohl, J. E., Huang, X. et al. 2019. Assessment of pain associated with the injection of sodium pentobarbital in laboratory mice (Mus musculus). JAALAS 58(3), 373-379.

The AVMA Guidelines for the Euthanasia of Animals considers injection of barbiturates to be an acceptable method of euthanasia in rodents but states there is a potential for pain when administered intraperitoneally. This study examined...

Moffitt, A. D., Brignolo, L. L., Ardeshir, A. et al. 2019. The role of emotional contagion in the distress exhibited by grouped mice exposed to CO2. JAALAS 58(4), 430-437.

The 2013 AVMA Guidelines for the Euthanasia of Animals recommends a chamber volume displacement rate of 10% to 30% per minute (v/min) when euthanizing small laboratory rodents with CO2. Group euthanasia of mice is a...

Leenaars, C. H. C., Pels, E. G. M., Joosten, R. N. J. M. A. et al. 2019. Wistar rats do not show preference for either of two commonly used nutritionally sound food rewards in a T-maze. Journal of Veterinary Behavior 31, 22-27.

Food rewards are commonly used as positive reinforcement in rodent behavioral experiments. Bioserv dustless precision pellets and Noyes formula P precision pellets are both used for this purpose in behavioral experiments in multiple laboratories, as...

ur Rahman, M. A., Xia, C., Ji, L. et al. 2019. Nutrient intake, feeding patterns, and abnormal behavior of growing bulls fed different concentrate levels and a single fiber source (corn stover silage). Journal of Veterinary Behavior 33, 46-53.

Twenty-eight bulls weighing 227 ± 6.8 (SD) kg were randomly assigned to four concentrate levels (1-1.5 kg [low level of concentrate {LC}], 1.5-2 kg [medium level of concentrate], 2-2.5 kg [high level of concentrate {HC}]...

Gjendal, K., Lund Ottesen, J., Olsson, I. A. S. et al. 2019. Burrowing and nest building activity in mice after exposure to grid floor, isoflurane or ip injections. Physiology & Behavior 206, 59-66.

Burrowing and nest building are examples of highly motivated innate behaviours in rodents. Assessments based on these behaviours can be used as non-invasive indicators of pain, distress and suffering. In this study, we investigated the...

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...

Gent, T. C., Detotto, C., Vyssotski, A. L. et al. 2018. Epileptiform activity during inert gas euthanasia of mice. PLOS ONE 13(4), e0195872.

Carbon dioxide (CO2) is one of the most commonly used euthanasia agents for mice, yet it is highly aversive and nociceptive. Inert gases are a possible alternative, however there are qualitative reports of seizures resulting...

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...

Gilliam, J. N., Woods, J., Hill, J. et al. 2018. Evaluation of the CASH Dispatch Kit combined with alternative shot placement landmarks as a single-step euthanasia method for cattle of various ages. Animal Welfare 27(3), 225-233.

Humane euthanasia of cattle under field conditions presents special challenges for veterinarians and producers. The purpose of this study was to evaluate the effectiveness of the CASH Dispatch Kit captive-bolt system combined with improved shot...

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...

Shearer, J. 2018. Euthanasia of cattle: Practical considerations and application. Animals 8(4), 57.

Acceptable methods for the euthanasia of cattle include overdose of an anesthetic, gunshot and captive bolt. The use of anesthetics for euthanasia is costly and complicates carcass disposal. These issues can be avoided by use...

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...