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. 
Alligood, C. A., Dorey, N. R., Mehrkam, L. R. et al. 2017. Applying behavior-analytic methodology to the science and practice of environmental enrichment in zoos and aquariums. Zoo Biology 36(3), 175–185.

Environmental enrichment in zoos and aquariums is often evaluated at two overlapping levels: published research and day‐to‐day institutional record keeping. Several authors have discussed ongoing challenges with small sample sizes in between‐groups zoological research and...

Damasceno, J., Genaro, G., Quirke, T. et al. 2017. The effects of intrinsic enrichment on captive felids. Zoo Biology 36(3), 186–192.

Environmental enrichment is a well‐known technique, which has been used to enhance the welfare of captive animals. The aim of this study is to investigate how three different forms of intrinsic enrichment, namely, a hay...

Simpson, D. 2017. Investigation of transportation on rat acclimatisation using novel cage side recording equipment (Rodent Big Brother). Animal Technology and Welfare 16(1), 1-12.

The transportation of animals from supplier to experimental facility is one of the biggest stressors to animals in research. Transportation unavoidably causes stress and when the animals arrive at the testing facility they require a...

Kleefeld, S., Bannerton, K., Kelly, J.2017. Effect of moderate environmental enrichment on commonly used behavioural tests in rats. Animal Technology and Welfare 16(1), 75-76.

The environment that laboratory animals are housed in should reflect their natural habitats in a manner that can satisfy their innate physiological and behavioural needs. This includes nest building, hiding, exploring and foraging. Providing environmental...

Jones, T., Robinson, M., Leach, M. et al. 2017. Ultrasonic vocalisation as a measure of positive welfare in rats. Animal Technology and Welfare 16(2), 127-129.

Studies of animal welfare in laboratory animals have historically relied on the measurement of negative indicators rather than the assessment of positive indicators of welfare. Practical methods of welfare assessment are required to allow refinement...

Spiezio, C., Leonardi, C., Regaiolli, B. 2017. Assessing colour preference in Aldabra giant tortoises (Geochelone gigantea). Behavioural Processes 145, 60-64.

Tortoises perceive different colours and rely on the visual system to find food. However, few studies have considered colour preference in tortoises, especially in land species. The aim of this study is to investigate whether...

Mármol, F., Sánchez, J., Torres, M. N. et al. 2017. Environmental enrichment in the absence of wheel running produces beneficial behavioural and anti-oxidative effects in rats. Behavioural Processes 144, 66-71.

The effects of early environmental enrichment (EE) when solving a simple spatial task in adult male rats were assessed. After weaning, rats were housed in pairs in enriched or standard cages (EE and control groups)...

Danner, L., Rao, V. P. 2017. Should rat enrichment devices be used beyond a month? Laboratory Animal Science Professional 5(1) (March), 41-43.

Enrichment devices made of materials such as nylon and wood are common gnawing devices used in animal facilities. In most institutions, these devices are used for a limited period and then discarded. At Pfizer, enrichment...

Rossi, N. 2017. The other 3Rs: Reduce, reuse, and recycle for rodents. Laboratory Animal Science Professional 5(1) (March), 44-46.

Since funding can be scarce, I seek novel and economical ways to promote the psychological wellbeing of the animals through environmental enrichment and allow research animals to express species-specific behaviors and control their environment to...

Slaney, H. 2017. Using domestic animals as tiger enrichment. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 44(2), 24-27.

At Colchester Zoo we have a well established but evolving enrichment program, using many different ideas and techniques for our many different species. One form of enrichment we use is the presence of our domestic...

Smith, B. L., Lyons, C. E., Correa, F. G. et al. 2017. Behavioral and physiological consequences of enrichment loss in rats. Psychoneuroendocrinology 77, 37-46.

Significant loss produces the highest degree of stress and compromised well-being in humans. Current rodent models of stress involve the application of physically or psychologically aversive stimuli, but do not address the concept of loss...

Monreal-Pawlowsky, T., Marco-Cabedo, V., Manteca, X. et al. 2017. Environmental enrichment facilitates release and survival of an injured loggerhead sea turtle (Caretta caretta) after ten years in captivity. Journal of Zoo and Aquarium Research 5(4), 182-186.

In June 2006 a loggerhead sea turtle (Caretta caretta) was admitted to a rescue centre on the Mediterranean coast with severe fishing net entanglement in its fore right flipper. The flipper could not be saved...

Li, K. A., Lund, E. T., Voigt, J.W. 2016. The impact of early postnatal environmental enrichment on maternal care and offspring behaviour following weaning. Behavioural Processes 122, 51-58.

The early postnatal period is a sensitive period in rodents as behavioural systems are developing and maturing during this time. However, relatively little information is available about the impact of environmental enrichment on offspring behaviour...

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...

Meehan, C. L., Hogan, J. N., Bonaparte-Saller, M. K. et al. 2016. Housing and social environments of African (Loxodonta africana) and Asian (Elephas maximus) elephants in North American zoos. PLOS ONE 11(7), e0146703.

We evaluated 255 African (Loxodonta africana) and Asian (Elephas maximus) elephants living in 68 North American zoos over one year to quantify housing and social variables. All parameters were quantified for the both the day...

Makowska, I. J., Weary, D. M. 2016. The importance of burrowing, climbing and standing upright for laboratory rats. Royal Society Open Science 3, 160136.

Standard laboratory cages prevent rats (Rattus norvegicus) from performing many behaviours that they perform in the wild, but little is known about how this may affect their welfare. The aims of this study were (i)...

Winnicker, C., Gaskill, B., Garner, J. P. et al. 2016. A Guide to the Behavior & Enrichment of Laboratory Rodents. Charles River Laboratories.

Covering species-typical behavior as well as abnormal/malfunctional behavior and stereotypes observed in mice, rats, hamsters and gerbils, this is an excellent resource for those looking to implement or enhance an existing behavioral husbandry and enrichment...

Bayne, K. A., Beaver, B. V., Mench, J. A. et al. 2015. Laboratory animal behavior. In: Laboratory Animal Medicine, 3rd edition. Fox, J. G., Anderson, L., Otto, G., et al. (eds). Elsevier, Inc., Amsterdam, NL. pp. 1617-1651.

The study of laboratory animal behavior has increased steadily over the last decade, with expanding emphasis on a variety of commonly used species. In the United States, this trend was initially focused on species for...

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...

Qi, K., De-mi, S., Chuan, Q. 2014. Current understanding and use of environmental enrichment in China. Enrichment Record 20, 8-11.

In practice, consideration is given to providing most of the species used in research,testing and education withsome level of environmental enrichment. However, although the current level of awareness and understanding about the benefits of environmental...

Lidfors, L., Wichman, A., Ewaldsson, B. et al. 2014. Enriched cages for groups of laboratory male rats and their effects on behaviour, weight gain and adrenal glands. Laboratory Animals 48, 36-49.

We investigated if there were any negative effects on the behaviour and physiology of rats housed in groups of five in two types of enriched cages and compared them with paired-housed rats housed in traditional...

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...

Ditewig, A. C., Bratcher, N. A., Davila, D. R. et al. 2014. Enrichment with wood blocks does not affect toxicity assessment in an exploratory toxicology model using Sprague-Dawley rats. JAALAS 53(3), 246-260.

Environmental enrichment in rodents may improve animal well-being but can affect neurologic development, immune system function, and aging. We tested the hypothesis that wood block enrichment affects the interpretation of traditional and transcriptomic endpoints in...