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. 
Améndola, L., Ratuski, A., Weary, D. M. 2021. Individual differences in rat sensitivity to CO2. PLOS ONE 16(1), e0245347.

Feelings of fear, anxiety, dyspnea and panic when inhaling carbon dioxide (CO2) are variable among humans, in part due to differences in CO2 sensitivity. Rat aversion to CO2 consistently varies between individuals; this variation in...

Lasky, M., Campbell, J., Osborne, J. A. et al. 2021. Increasing browse and social complexity can improve zoo elephant welfare. Zoo Biology 40(1), 9–19.

While recent work has assessed how environmental and managerial changes influence elephant welfare across multiple zoos, few studies have addressed the effects of management changes within a single institution. In this paper, we examine how...

Sørensen, D., Cloutier, S., Gaskill, B. (Eds.). 2021. Animal-centric Care and Management - Enhancing Refinement in Biomedical Research. CRC Press, Boca Raton, FL.

The concept of the 3Rs (Refinement, Reduction and Replacement) has been used as a framework for improving the welfare of laboratory animals for the last half century. By establishing an animal-centric view on housing and...

Perea, C., Vázquez-Ágredos, A., Ruiz-Leyva, L. et al. 2021. Caloric restriction in group-housed mice: Littermate and sex influence on behavioral and hormonal data. Frontiers in Veterinary Science 8, 639187.

Much of the research done on aging, oxidative stress, anxiety, and cognitive and social behavior in rodents has focused on caloric restriction (CR). This often involves several days of single housing, which can cause numerous...

Krueger, L. D., Chang, S. E., Motoc, M. et al. 2021. Effects of pair housing on patency of jugular catheters in rats (Rattus norvegicus). JAALAS 60(3), 357-364.

Chronic vascular access devices are widely used in a variety of species for repeated blood sampling or substance administration. Jugular catheters are commonly used for studying addiction-related behaviors in rats. Rats with catheters have historically...

Yu, J. H., Brown, J., Boisseau, N. et al. 2021. Effects of Lupron and surgical castration on fecal androgen metabolite concentrations and intermale aggression in capybaras (Hydrochoerus hydrochaeris). Zoo Biology 40(2), 135-141.

To curb agonistic interactions in a bachelor group of three male capybaras (Hydrochoerus hydrochaeris), a single dose of leuprolide acetate (Lupron®) was used in an attempt to chemically sterilize the males. Concurrently, fecal androgen metabolite...

Rodriguez-Sanchez, R., Barnaby, E., Améndola, L. et al. 2021. Voluntary oral ingestion of a sedative prior to euthanasia with CO2: Behavioural responses of mice. Animals 11(10), 2879.

Laboratory mice are commonly euthanised with carbon dioxide (CO2); however, there is ample evidence that this gas is aversive. Previous work suggests that sedation achieved via injection with benzodiazepines prior to CO2 administration could reduce...

Hörner, F., Oerke, A.-K., Müller, D. W. H. et al. 2021. Monitoring behaviour in African elephants during introduction into a new group: Differences between related and unrelated animals. Animals 11(10), 2990.

The introduction of elephants into new groups is necessary for breeding programmes. However, behavioural studies on the reactions of these animals at first encounters are missing. In the present study, female African elephants (Loxodonta africana)...

Buckinx, A., Van Schuerbeek, A., Bossuyt, J. et al. 2021. Exploring refinement strategies for single housing of male C57BL/6JRj mice: Effect of cage divider on stress-related behavior and hypothalamic-pituitary-adrenal-axis activity. Frontiers in Behavioral Neuroscience 15, 743959.

Introduction: Single housing of laboratory mice is a common practice to meet experimental needs, or to avoid intermale aggression. However, single housing is considered to negatively affect animal welfare and may compromise the scientific validity...

da Silva Medeiros Elidio, H., Coelho, J. W. R., Cavalcanti Pereira da Silva, L. C. et al. 2021. Housing density and aggression in Syrian hamsters. JAALAS 60(5), 506-509.

The Syrian hamster (Mesocricetus auratus) is a solitary and naturally territorial animal, with female hamsters being more aggressive than males. This behavior makes handling difficult because they are usually housed in groups, which can lead...

Brunt, M. W., Améndola, L., Weary, D. M. 2021. Attitudes of laboratory animal professionals and researchers towards carbon dioxide euthanasia for rodents and perceived barriers to change. Laboratory Animals 55(6), 531-539.

Evidence indicates that carbon dioxide (CO2) induces negative affective states (including anxiety, fear and distress) in laboratory rodents, but many countries still accept it for euthanasia. Alternative methods (e.g. inhalant anaesthetic) may represent a refinement...

Locklear, J., Whiteside, T. E. 2021. Optimal colloidal water gel type and novel placement for frequent travelers. Laboratory Animal Science Professional 9(6) (November/December), 38-40.

During transportation, animals must have a water source available to prevent dehydration. Some shipping facilities use potatoes whereas, others use colloidal water gels that provide a uniform water source. The problem occurs when colloidal water...

Wilkin, M. M., Menard, J. L. 2020. Social housing ameliorates the enduring effects of intermittent physical stress during mid-adolescence. Physiology & Behavior 214, 112750.

Our prior work showed that exposing single housed rats to intermittent physical stress (IPS) in mid-adolescence (PD35-46) led to increased risk-taking/decreased anxiety behaviour in adulthood, as indexed by their greater willingness to explore the open-arms...

Persson, K., Selter, F., Neitzke, G. et al. 2020. Philosophy of a “good death” in small animals and consequences for euthanasia in animal law and veterinary practice. Animals 10(1), 124.

Moral stress is a major concern in veterinary practice. Often, it is associated with the challenges in end-of-life situations. Euthanasia, however, is also meant to bring relief to animal patients and their owners. The reasons...

Gades, N. M., Thompson, K. L., Mi, L. et al. 2020. Impact of euthanasia on compassion fatigue in personnel working in animal research. Laboratory Animal Science Professional 8(1) (January/February), 22-23.

We conducted a cross-sectional study to investigate the association between euthanasia and compassion fatigue among employees working in animal research at a large academic medical center. In summary, animal research workers who euthanize animals reported...

Insel, N., Shambaugh, K. L., Beery, A. K. 2020. Female degus show high sociality but no preference for familiar peers. Behavioural Processes 174, 104102.

Group-living animals vary in social behavior across multiple dimensions, including in the selectivity of social interactions with familiar versus unfamiliar peers. Standardized behavioral tests can be used to tease apart different dimensions of behavior. These...

da Silva, A., Lima, M. R., Meletti, P. C. et al. 2020. Impact of environmental enrichment and social group size in the aggressiveness and foraging activity of Serrapinnus notomelas. Applied Animal Behaviour Science 224, 104943.

Fish are widely used in scientific research, and many species are bred for ornamental purposes and human consumption. Despite the large number of fish kept in captivity, research on the welfare of these animals has...

Harrup, A. J., Rooney, N. 2020. Current welfare state of pet guinea pigs in the UK. Veterinary Record 186(9), 282.

Little research has been carried out into how guinea pigs are cared for in the UK, and information regarding potential welfare issues is sparse. This study was designed to examine the five welfare needs, collecting...

Peterman, J.L., White, J.D., Calcagno, A. et al. 2020. Prolonged isolation stress accelerates the onset of Alzheimer’s disease-related pathology in 5xFAD mice despite running wheels and environmental enrichment. Behavioural Brain Research 379, 112366.

Research has demonstrated that stress can exacerbate AD pathology in transgenic mouse models of AD. The purpose of the present studies was to extend this work by determining whether a social stressor, isolation stress, would...

Veasey, J. 2020. Assessing the psychological priorities for optimising captive Asian elephant (Elephas maximus) welfare. Animals 10(1), 39.

The welfare status of elephants under human care has been a contentious issue for two decades or more in numerous western countries. Much effort has gone into assessing the welfare of captive elephants at individual...

Frost, K., Shah, M., Leung , V. S. Y. et al. 2020. Aversion to desflurane and isoflurane in Sprague-Dawley rats (Rattus norvegicus). Animals 10(6), 950.

Carbon dioxide and isoflurane are widely used for killing rats, yet may not truly achieve “euthanasia”, because they elicit aversion. The inhalant anesthetic desflurane is faster acting than isoflurane, representing a potential refinement. Using an...

Ballantine, A., Rodgers, D., Watts, C. et al. 2020. The cotton rat – a new challenge. Animal Technology and Welfare 19(1), 92-95.

This poster describes how the Animal Technologists at Envigo adapted their current practices and procedures for a new species at their laboratory: the cotton rat. The paper describes cotton rat biology and behaviour; housing; environmental...

Reading, P., Reading, R., Branstone, C. 2020. Mirror, mirror, on the wall. Animal Technology and Welfare 19(1), 98-100.

When mice are grouped together for the first time, it is a novel experience filled with new sights and smells that will stress the animal too much and may cause aggression. By adding a mirror...

Améndola, L., Weary, D. M. 2020. Understanding rat emotional responses to CO2. Translational Psychiatry 10, 253.

The aim of this review is to summarize evidence regarding rat emotional experiences during carbon dioxide (CO2) exposure. The studies reviewed show that CO2 exposure is aversive to rats, and that rats respond to CO2...

Chu, D. 2020. Malawi cichlids: A colorful 4th R story. Laboratory Animal Science Professional 8(3) (May/June), 24-25.

This article describes the successful rehoming of 60 Malawi cichlids from a vivarium at Stanford University to San Diego Zoo and the California Academy of Sciences.