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. 
Johnson, S. R., Patterson-Kane, E. G. 2003. Foraging as environmental enrichment for laboratory rats: A theoretical review. Animal Technology and Welfare 2, 13-22.

Foraging opportunities are a form of environmental enrichment with great potential to improve the welfare of animals in laboratories. Though commonly used with zoo animals, little evidence exists of their use in laboratories. Technicians or...

Applebee, K. A. 2002. Rodent environmental enrichment - animal welfare or human feel-good factor. Animal Technology and Welfare 1(2), 65-69.

This article discusses environmental enrichment for rodents, mainly mice and rats housed in conventional caging, in U.K. research facilities. Environmental enrichment should allow and encourage animals to perform normal behavioural patterns. Cage furniture cannot be...

Olsson, I. A. S., Dahlborn, K. 2002. Improving housing conditions for laboratory mice: A review of 'environmental enrichment'. Laboratory Animals 36, 243-270.

We have reviewed 40 studies carried out between 1987 and 2000, in which preferences as well as the effect of housing modifications have been studied. Mice will work for access to nesting material and make...

Fernández-Teruel, A., Giménez-Llort, L., Escorihuela, R. M. et al. 2002. Early-life handling stimulation and environmental enrichment: Are some of their effects mediated by similar neural mechanisms? Pharmacology Biochemistry and Behavior 73(1), 233-245.

Neonatal (early) handling (EH) and environmental enrichment (EE) of laboratory rodents have been the two most commonly used methods of providing supplementary environmental stimulation in order to study behavioral and neurobiological plasticity. A large body...

Cohoon, J. 2001. Nylabone on a chain. Tech Talk [The Newsletter for Laboratory Animal Science Technicians] 6(1), 2.

Both pigs and rabbits are having a great time banging the bone on the cage - they can swing it around, and they get to chew on it too!

Raje, S. S., Stewart, K. L. 2000. Group housing female guinea pigs. Lab Animal 29(8), 31-32.

Group housing [female] guinea pigs can save space and money, while improving housing standards. The authors describe enclosure design, enrichments, and husbandry techniques that facilitate group housing female guinea pigs. No data are included in...

Menke, C., Waiblinger, S., Fölsch, D. W. et al. 1999. Social behaviour and injuries of horned cows in loose housing systems. Animal Welfare 8, 243-258.

The results of the present study show that keeping horned dairy cows in loose housing systems is possible without unacceptable risks for cows and humans. However, it is absolutely necessary to optimize herd management conditions...

Eskola, S., Lauhikari, M., Voipio, H.-M. et al. 1999. Environmental enrichment may alter the number of rats needed to achieve statistical significance. Scandinavian Journal of Laboratory Animal Science 26(3), 134-144.

The aim of this study was to evaluate whether two enrichment items, an aspen tube and block, have any impact on commonly analysed clinical chemistry and physiological parameters of Wistar rats and - more importantly...

Eskola, S., Lauhikari, M., Voipio, H.-M. et al. 1999. The use of aspen blocks and tubes to enrich the cage environment of laboratory rats. Scandinavian Journal of Laboratory Animal Science 26(1), 1-10.

Female and male outbred Wistar rats (n=48) were allocated into three groups at weaning; control, tube and block groups (n = 8 males and 8 females in each) Animals were conventionally housed for five weeks...

Fullwood, S., Hicks, T. A., Brown, J. C. et al. 1998. Floor space needs for laboratory mice: C57BL/6 males in solid-bottom cages with bedding. ILAR Journal 39(1), 29-36.

Different floor space allocations of cages that were barren except bedding were tested in groups of 3 male mice. Space reduction - from 129 to 32 square cm per mouse - had no impact on...

Eskola, S., Kaliste-Korhonen, E. 1998. Effects of cage type and gnawing blocks on weight gain, organ weights and open-field behaviour inWistar rats. Scandinavian Journal of Laboratory Animal Science 25(4), 180-193.

Two separate experiments were conducted to study the environmental enrichment value of aspen gnawing blocks in solid bottom cages with bedding '(SBC) and in grid floor cages without bedding (GFC), and the effects of housing...

Benefiel, A. C., Greenough, W. T. 1998. Effects of experience and environment on the developing and mature brain: Implications of laboratory animal housing. ILAR Journal 39(1), 5-11.

Immune system function appears to be enhanced in environmentally enriched rats relative to controls housed in standard cages.

Pecenko, N. 1997. Visitors as an environmental enrichment. In: Proceedings on the International Conference on Environmental Enrichment. Holst, B. (ed), 325-33. Copenhagen Zoo, Frederiksberg, DK.

Because of the influence in behaviour, we can say that visitors are a kind of environmental enrichment. .... Sometimes visitors have a negative effect (increase of aggressive behaviour, begging for food) and in some cases...

Kaliste-Korhonen, E., Kelloniemi, J., Harri, M. 1996. Cage material and rat behaviour. Scandinavian Journal of Laboratory Animal Science 23(Supplement 1), 125-128. (Conference Paper)
Dahlborn, K., van Gils, B. A. A., van de Weerd, H. A. et al. 1996. Evaluation of long-term environmental enrichment in the mouse. Scandinavian Journal of Laboratory Animal Science 23(Supplement 1), 97-106. (Conference Paper)

It appears that mice who were enriched with both objects [nest box and plastic tube] and nesting material were more active, and spent less time on feeding and drinking, and they weight less compared to...

Burghardt, G. M., Ward, B., Rosscoe, R. 1996. Problem of reptile play: Environmental enrichment and play behavior in a captive Nile soft‐shelled turtle, Trionyx triunguis. Zoo Biology 15(3), 223-238.

Giving captive animals the opportunity to interact with objects in a “playful” manner is often considered a method of environmental enrichment. However, the occurrence of play in nonavian reptiles is controversial and poorly documented. Similarly...

Van den Broek, F. A. R., Klompmaker, H., Bakkere, R. et al. 1995. Gerbils prefer partially darkened cages. Animal Welfare 4, 119-123.

Little is known about housing requirements of gerbils. ... The ten animals included in the [preference] test spent most of their time in the cages that were darkened by 50 and 75 per cent, thus...

Kaliste-Korhonen, E., Eskola, S., Rekilä, T. et al. 1995. Effects of gnawing material, group size and cage level in rack on Wistar rats. Scandinavian Journal of Laboratory Animal Science 22(4), 291-299.

Han:Wist rats were housed after weaning in groups of one, two, three or four in stainless steel cages with aspen chip bedding, with or without wooden gnawing blocks. The use of the blocks was assessed...

Wurbel, H., Stauffacher, M. 1994. Standard-Haltung fur Labormause - Probleme und Losungsasatze. Tierlaboratorium 17, 109-118.

The high prevalence of stereotypies in mice kept in standard animal facilities is underscored.

Pough, F. H. 1991. Recommendations for the care of amphibians and reptiles in academic institutions. ILAR Journal 33(4), S1-S21.

Amphibians and reptiles differ in many respects from the mammals and birds most commonly used in biomedical research. These differences affect the physical and biological requirements of amphibians and reptiles in captivity. In this contribution...

Love, J. A. 1988. Housing for rabbits. Humane Innovations and Alternatives in Animal Experimentation 2, 47-48.

In most laboratory situations, rabbits are kept isolated in cages. ... We have attempted to correct this deficiency by keeping rabbits in either large tubs which can accommodate six or more animals or in indoor/outdoor...

Gray, G. 1988. Guinea pigs. Humane Innovations and Alternatives in Animal Experimentation 2, 48-49.

Initial attempts to provide the animals a covered area for refuge showed that the guinea pigs adopted the shelter very quickly and would dart under cover when startled. ... We soon realized that this was...

Boyd, J. 1988. Mice. Humane Innovations and Alternatives in Animal Experimentation 2, 49-50.

Description of an ingenious, simple method to minimize odor, provide species-appropriate nesting opportunities and to facilitate cleaning.

Mantel, N. 1980. Assessing laboratory evidence for neoplastic activity. Biometics 36, 381-399.

Mortality and tumor incidence in corcinogenesis experiments differ between mice caged in the top vs. bottom of the rack.

Gutwein, B. M., Fishbein, W. 1980. Paradoxical sleep and memory (I): Selective alterations following enriched and impoverished environmental rearing. Brain Research Bulletin 5(1), 9-12.

Mice were reared in either enriched (EE), social control, (SE), or impoverished (IE) environments for 30 days. Environmental enrichment results in a significant and selective increase in paradoxical sleep (PS, or REM sleep) and also...