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. 
Buchanan, K. 2020. DIY: Foraging balls. Laboratory Animal Science Professional 8(3) (May/June), 51.

This article describes the steps for making a DIY guinea pig or rabbit cardboard foraging ball. Pictures are provided for each step as well as the completed ball. These cardboard foraging balls can be made...

Hambrecht, S., Oerke, A.‐K., Heistermann, M. et al. 2020. Diurnal variation of salivary cortisol in captive African elephants (Loxodonta africana) under routine management conditions and in relation to a translocation event. Zoo Biology 39(3), 186–196.

The present study assessed the diurnal variation in salivary cortisol in captive African elephants during routine management (baseline) and in relation to a potential stressor (translocation) to evaluate to what extent acute stress may affect...

Turner, P. V., Hickman, D. L., van Luijk, J. et al. 2020. Welfare impact of carbon dioxide euthanasia on laboratory mice and rats: A systematic review. Frontiers in Veterinary Science 7, 411.

Background: There has been increased concern about the suitability of CO2 as a method for euthanasia of laboratory mice and rats, including the potential discomfort, pain or distress that animals may experience prior to loss...

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...

Blackburn, N., Cronshaw, G., Mitchell, M. 2020. Environmental enrichment for a small colony of rats. Animal Technology and Welfare 19(2), 158.

Due to limited space and resource for equipment, we came up with some easy and cost-effective ways to improve enrichment for the rat colony. Since implementing our protocol for forage feeding and out of cage...

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...

Khoo, S. Y.-S., Correia, V., Uhrig, A. 2020. Nesting material enrichment reduces severity of overgrooming-related self-injury in individually housed rats. Laboratory Animals 54(6), 546-558.

Individual or singly-housing laboratory rats is common in many animal facilities, but has an adverse impact on the welfare of this social species. It has previously been shown that a small proportion of individually housed...

Worlds, T., Kearney, M., De La Garza, F. et al. 2020. Development of a rabbit enrichment program and contribution to a culture of transparency and care. Laboratory Animal Science Professional 8(6) (November/December), 38-40.

The Becton Dickinson (BD) Research Animal Care Program has developed an acclimation and enrichment program that has enhanced animal welfare for studies requiring single housing, contributed to a culture of care, increased transparency, and improved...

Gabriel, P., Mastracchio, T., Bordner, K. et al. 2020. Impact of enriched environment during adolescence on adult social behavior, hippocampal synaptic density and dopamine D2 receptor expression in rats. Physiology & Behavior, 226, 113133.

Environmental enrichment (EE) is one experimental manipulation that induces changes in the brain. However, it is important to distinguish between physical and social components of enrichment. To this end we established four groups of rats...

Keymoradzadeh, A., Hedayati Ch, M., Abedinzade, M. et al. 2020. Enriched environment effect on lipopolysaccharide-induced spatial learning, memory impairment and hippocampal inflammatory cytokine levels in male rats. Behavioural Brain Research 394, 112814.

Neuro-inflammation is responsible for cognitive impairments and neurodegenerative diseases such as Alzheimer’s disease. In this study, we aimed to investigate the enriched environment (EE) effect on learning and memory impairment as well as on pro-inflammatory...

Lang, G. P. S. A., Rose, P. E., Nash, S. M. et al. 2020. The nocturnal activity of a commonly housed rodent: How African pygmy dormice (Graphiurus murinus) respond to an enriched environment? Journal of Veterinary Behavior 38, 82-88.

Exotic rodents are becoming increasingly popular in industry; however, there is limited empirical evidence to guide husbandry practices. African pygmy dormice (Graphiurus murinus) are typical in this respect. This research aimed to determine the effect...

Modlinska, K., Chrzanowska, A., Pisula, W. 2020. Variability of enriched environment does not enhance the enrichment effect on food neophobia in rats (Rattus norvegicus). Behavioural Processes 180, 104221.

Many studies report differences between animals raised in an enriched environment and those living in standard conditions. Animals reared in enriched conditions demonstrate better memory and learning abilities, increased activity, reduced level of anxiety, etc...

Natusch, D. J. D., Aust, P. W., Khadiejah, S. et al. 2020. Behavioral and corticosterone responses to carbon dioxide exposure in reptiles. PLOS ONE 15(10), e0240176.

The use of carbon dioxide (CO2) exposure as a means of animal euthanasia has received considerable attention in mammals and birds but remains virtually untested in reptiles. We measured the behavioral responses of four squamate...

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...

McMahon, S. A., Wigham, E. 2020. ‘All Ears’: A questionnaire of 1516 owner perceptions of the mental abilities of pet rabbits, subsequent resource provision, and the effect on welfare. Animals 10(10), 1730.

Pet rabbit welfare is a hidden crisis: Inappropriately housed, fed, and not routinely provided healthcare—rabbits can often suffer painful conditions and shortened lifespans. This study provides novel understanding of owners’ perceptions of rabbits’ mental capabilities...

Coda, K. A., Fortman, J. D., García, K. D. 2020. Behavioral effects of cage size and environmental enrichment in New Zealand white rabbits. JAALAS 59(4), 356-364.

One of the goals of environmental enrichment is to encourage species-typical behaviors, while discouraging abnormal behaviors or stereotypies. Assessing the effectiveness of various enrichment modalities can be challenging, particularly for prey species such as rabbits...

Rojas-Carvajal, M., Sequeira-Cordero, A., Brenes, J. C. 2020. Neurobehavioral effects of restricted and unpredictable environmental enrichment in rats. Frontiers in Pharmacology 11, 674.

To study how motivational factors modulate experience-dependent neurobehavioral plasticity, we modify a protocol of environmental enrichment (EE) in rats. We assumed that the benefits derived from EE might vary according to the level of incentive...

Pisula, W., Modlinska, K., Chrzanowska, A. 2019. Behavioural response to the environmental changes of various types in Lister-Hooded male rats. Scientific Reports 9, 7111.

The animal preference for complexity is most clearly demonstrated when the environmental change takes the form of an increase in complexity. Therefore, one of the potential difficulties in interpretation is that the preference for perceptual...

Eagan, T. 2019. Evaluation of enrichment for reptiles in zoos. Journal of Applied Animal Welfare Science 22(1), 69-77.

Studies on environmental enrichment for reptiles are lacking in the scientific literature. Although the literature reflects a limited take on reptile enrichment in the zoological community, it may not be the case in reality as...

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...

Mastellone, V., Bovera, F., Musco, N. et al. 2019. Mirrors improve rabbit natural behavior in a free-range breeding system. Animals 9(8), 533.

The aim of this research was to evaluate the possible usefulness of mirrors in improving rabbit behavior in a free-range breeding system. Three groups (each consisting of nine replicates of three animals) were compared: isolated...

Trocino, A., Zomeño, C., Filiou, E. et al. 2019. The use of environmental enrichments affects performance and behavior of growing rabbits housed in collective pens. Animals 9(8), 537.

This study assessed the effects of an elevated plastic-slatted platform and/or a plastic hiding tube in collective pens with large group sizes (27 or 36 rabbits/pen; 16 rabbits/m2) on the performance and welfare of rabbits...