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. 
Brown, J. L., Paris, S., Prado-Oviedo, N. A. 2016. Reproductive health assessment of female elephants in North American zoos and association of husbandry practices with reproductive dysfunction in African Elephants (Loxodonta africana). PLOS ONE 11(7), e0145673.

As part of a multi-institutional study of zoo elephant welfare, we evaluated female elephants managed by zoos accredited by the Association of Zoos and Aquariums and applied epidemiological methods to determine what factors in the...

Makowska, I. J., Weary, D. M. 2016. Differences in anticipatory behaviour between rats (Rattus norvegicus) housed in standard versus semi-naturalistic laboratory environments. PLOS ONE 11(1), e0147595.

Laboratory rats are usually kept in relatively small cages, but research has shown that they prefer larger and more complex environments. The physiological, neurological and health effects of standard laboratory housing are well established, but...

Holdgate, M. R., Meehan, C. L., Hogan, J. N. et al. 2016. Walking behavior of zoo elephants: Associations between GPS-measured daily walking distances and environmental factors, social factors, and welfare indicators. PLOS ONE 11(7), e0150331.

Research with humans and other animals suggests that walking benefits physical health. Perhaps because these links have been demonstrated in other species, it has been suggested that walking is important to elephant welfare, and that...

Holdgate, M. R., Meehan, C. L., Hogan, J. N. et al. 2016. Recumbence behavior in zoo elephants: Determination of patterns and frequency of recumbent rest and associated environmental and social factors. PLOS ONE 11(7), e0153301.

Resting behaviors are an essential component of animal welfare but have received little attention in zoological research. African savanna elephant (Loxodonta africana) and Asian elephant (Elephas maximus) rest includes recumbent postures, but no large-scale investigation...

Miller, M. A., Hogan, J. N., Meehan, C. L. 2016. Housing and demographic risk factors impacting foot and musculoskeletal health in African elephants [Loxodonta africana] and Asian elephants [Elephas maximus] in North American zoos. PLOS ONE 11(7), e0155223.

For more than three decades, foot and musculoskeletal conditions have been documented among both Asian [Elephas maximus] and African [Loxodonta africana] elephants in zoos. Although environmental factors have been hypothesized to play a contributing role...

Prado-Oviedo, N. A., Bonaparte-Saller, M. K., Malloy, E. J. et al. 2016. Evaluation of demographics and social life events of Asian (Elephas maximus) and African elephants (Loxodonta africana) in North American zoos. PLOS ONE 11(7), e0154750.

This study quantified social life events hypothesized to affect the welfare of zoo African and Asian elephants, focusing on animals that were part of a large multi-disciplinary, multi-institutional elephant welfare study in North America. Age...

Morfeld, K. A., Meehan, C. L., Hogan, J. N. et al. 2016. Assessment of body condition in African (Loxodonta africana) and Asian (Elephas maximus) elephants in North American zoos and management practices associated with high body condition scores. PLOS ONE 11(7), e0155146.

Obesity has a negative effect on health and welfare of many species, and has been speculated to be a problem for zoo elephants. To address this concern, we assessed the body condition of 240 elephants...

Koontz, J. M., Kumsher, D. M., Kelly, R. 3rd et al. 2016. Effect of 2 bedding materials on ammonia levels in individually ventilated cages. JAALAS 55(1), 25–28.

This study sought to identify an optimal rodent bedding and cage-change interval to establish standard procedures for the IVC in our rodent vivarium. Disposable cages were prefilled with either corncob or α-cellulose bedding and were...

Sullivan, K., Kerr, K., Wanty, R. et al. 2016. Dietary management, husbandry, and body weights of African elephants (Loxodonta africana) during successful pregnancies at Disney's Animal Kingdom. Zoo Biology 35(6), 574-578.

Successful pregnancy in African elephants is influenced by biological and environmental factors. For managed elephants many of these factors are set directly or indirectly by their human care takers, including nutrition and husbandry. While African...

Abou-Ismail, U. A., Mohamed, R. A., El-Kholya, S. Z. 2015. The effects of witnessing managemental procedures during the light versus the dark phase of the light cycle on behaviour, performance and welfare of laboratory rats. Applied Animal Behaviour Science 162, 47-57.

Research has indicated that witnessing managemental procedures are stressful to laboratory rats. Yet there has been little investigation into whether the time of witnessing these procedures affects behaviour and welfare in these animals. Ninety-six rats...

Pritchett-Corning, K. R., Gaskill, B. N. 2015. Lack of negative effects on Syrian hamsters and Mongolian gerbils housed in the same secondary enclosure. JAALAS 54(3), 261-266.

In cases where different species might be housed in the same room or secondary enclosure, the Guide for the Care and Use of Laboratory Animals recommends that the animals should be behaviorally compatible and have...

Heyse, N. C., Brenes, J. C., Schwarting, R. K. W. 2015. Exercise reward induces appetitive 50-kHz calls in rats. Physiology & Behavior 147, 131-140.

Rats express affective states by visible behaviors (like approach or flight) and through different kinds of ultrasonic vocalizations (USV). 50-kHz calls are thought to reflect positive affective states since they occur during rewarding situations like...

Bethell, E. J., Koyama, N. F. 2015. Happy hamsters? Enrichment induces positive judgement bias for mildly (but not truly) ambiguous cues to reward and punishment in Mesocricetus auratus. Royal Society Open Science 2, 140399.

Recent developments in the study of animal cognition and emotion have resulted in the ‘judgement bias’ model of animal welfare. Judgement biases describe the way in which changes in affective state are characterized by changes...

Sorensen, D. B. 2014. Shedding ultraviolet light on welfare in laboratory rodents: Suggestions for further research and refinement. Animal Welfare 23(3), 259-261.

The welfare of laboratory rats and mice is sought to be optimised through adjustment of a variety of environmental factors, including light intensity and photoperiodicity. However, the fact that rodents are able to perceive ultraviolet...

Holley, A., Drayer, J., Rammling, M. et al. 2014. A simplified method to identify and reduce flooded rodent caging. Charles River, Orlando, FL.

The number of flooded cages per cage change cycle (14 days) was tracked and it was identified that leaks and flooding often times occurred shortly after cage changing. To reduce the occurrence of flooded caging...

Escribano, B., Quero, I., Feijóo, M. et al. 2014. Role of noise and music as anxiety modulators: Relationship with ovarian hormones in the rat. Applied Animal Behaviour Science 152, 73-82.

This work aims to verify the role of noise and music as anxiety modulators and their relationship with ovarian hormones. For this purpose, female Wistar rats were used and treated, forming different experimental groups, with...

Bartal, I. B.-A., Rodgers, D. A., Sarria, M. S. et al. 2014. Pro-social behavior in rats is modulated by social experience. eLife 3, e01385.

In mammals, helping is preferentially provided to members of one’s own group. Yet, it remains unclear how social experience shapes pro-social motivation. We found that rats helped trapped strangers by releasing them from a restrainer...

Jones, C. E., Riha, P. D., Gore, A. C. et al. 2014. Social transmission of Pavlovian fear: Fear-conditioning by-proxy in related female rats. Animal Cognition 17(3), 827–834.

Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a foot-shock) leads to associative learning such that the tone alone will elicit a conditioned response (e.g., freezing)...

Makowska, I. J., Weary, D. M. 2013. Assessing the emotions of laboratory rats. Applied Animal Behaviour Science 148, 1-12.

Rats are one of the most commonly used species in research, and decades of testing have yielded a large amount of information pertaining to their experience of emotion. The aim of this review is to...

Posadas, M., Neubauer, T., Buckmaster, C. A. 2013. Noisy construction does not have to generate noisy data. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 670-671 (Abstract).

Our institution opened the Jan and Dan Duncan Neurologic Research Institute (NRI) in November of 2010. This facility houses a team of world renowned researchers working with mice and rats to develop treatments for childhood...

Hrapkiewicz, K., Colby, L. A., Denison, P. 2013. Clinical Laboratory Animal Medicine: An Introduction (4th Ed). Wiley-Blackwell, Ames, IA.

Clinical Laboratory Animal Medicine: An Introduction, Fourth Edition offers a user-friendly guide to the unique anatomy and physiology, care, common diseases, and treatment of small mammals and nonhuman primates. Carefully designed for ease of use...

Boivin, G. P. 2013. Availability of feces-free areas in rodent shoebox cages. Lab Animal 42(4), 135-141.

The Guide for the Care and Use of Laboratory Animals (the Guide) recommends that terrestrial mammals be provided space free of urine and feces in which to rest. To evaluate the feasibility of meeting this...

Severs, E., Leszcynski, J. 2012. Training rats to shift into clean cages by using operant conditioning with positive reinforcement. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 632-633 (Abstract #PS8).

Changing soiled cages is an integral part of husbandry, yet it can be a source of stress for both animal and animal care technician. In one case, large geriatric rats weighing around 1 kg did...

Leys, L. J., McGaraughty, S., Radek, R. J. 2012. Rats housed on corncob bedding show less slow-wave sleep. JAALAS 51(6), 764-768.

Despite the reported advantages of corncob bedding, questions have emerged about how comfortable animals find this type of bedding as a resting surface. In this study, encephalography (EEG) was used to compare the effects of...

Horn, M. J., Hudson, S. V., Bostrom, L. A. et al. 2012. Effects of cage density, sanitation frequency, and bedding type on animal well-being and health and cage environment in mice and rats. JAALAS 51(6), 781-788.

Ongoing studies and historical data support the finding that deviations or exceptions from the cage density and sanitation frequency standards set forth in the Guide do not negatively affect animal health, welfare, or production parameters...