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. 
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...

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...

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...

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...

Yamanashi, Y., Teramoto, M., Morimura, N. et al. 2016. Effects of relocation and individual and environmental factors on the long-term stress levels in captive chimpanzees (Pan troglodytes): Monitoring hair cortisol and behaviors. PLOS ONE 11(7), e0160029.

Understanding the factors associated with the long-term stress levels of captive animals is important from the view of animal welfare. In this study, we investigated the effects of relocation in addition to individual and environmental...

de Groot, B., Cheyne, S. M. 2016. Does mirror enrichment improve primate well-being? Animal Welfare 25(2), 163-170.

Primates are highly social animals and appropriate enrichment is required to ensure their psychological well-being. Mirrors are sometimes used as social or sensory environmental enrichment. In this paper we investigate the suitability of mirrors as...

Valentim, A. M., Guedes, S. R., Pereira, A. M. et al. 2016. Euthanasia using gaseous agents in laboratory rodents. Laboratory Animals 50(4), 241-253.

Several questions have been raised in recent years about the euthanasia of laboratory rodents. Euthanasia using inhaled agents is considered to be a suitable aesthetic method for use with a large number of animals simultaneously...

Hawkins, P., Prescott, M., Carbone, L. et al. 2016. A good death? Report of the second Newcastle meeting on laboratory animal euthanasia. Animals 6(9), 50.

Millions of laboratory animals are killed each year worldwide. There is an ethical, and in many countries also a legal, imperative to ensure those deaths cause minimal suffering. However, there is a lack of consensus...

Hickman, D., Fitz, S., Bernabe, C. et al. 2016. Evaluation of low versus high volume per minute displacement CO2 methods of euthanasia in the induction and duration of panic-associated behavior and physiology. Animals 6(8), 45.

Current recommendations for the use of CO 2 as a euthanasia agent for rats require the use of gradual fill protocols (such as 10% to 30% volume displacement per minute) in order to render the...

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)...

Sakuraba, Y., Tomonaga, M., Hayashi, M. 2016. A new method of walking rehabilitation using cognitive tasks in an adult chimpanzee (Pan troglodytes) with a disability: A case study. Primates 57(3), 403-412.

There are few studies of long-term care and rehabilitation of animals which acquired physical disabilities in captivity, despite their importance for welfare. An adult male chimpanzee named Reo at the Primate Research Institute of Kyoto...

Hooper, L. M., Shender, M. A., Ross, S. R. 2016. Behavioral research as physical enrichment for captive chimpanzees. Zoo Biology 34(4), 293-297.

In this study, we evaluated the potential for a behavioral research study, designed to evaluate chimpanzee decision‐making behavior, to also encourage increased activity in a group of zoo‐housed chimpanzees. For the behavioral study, the chimpanzees...

Enser, S. 2016. Comparison of housing and welfare of group housed rabbits. Animal Technology and Welfare 15(1), 77-79.

This poster is based on welfare improvements gained from group housing rabbits in floor pens in the new Antibody Production Facility with a focus on development, behaviours and environmental enrichment in both male and female...

O'Keefe, S. 2016. Non-human primate housing facility at Newcastle University. Animal Technology and Welfare 15(2), 131-132.

Monkeys first arrived in the Comparative Biology Centre (CBC) at Newcastle University in 2000. They were housed in three small separate units consisting of steel and wooden cages. In 2011 a decision was made to...

Kim-McCormack, N. N. E., Smith, C. L., Behie, A. M. 2016. Is interactive technology a relevant and effective enrichment for captive great apes? Applied Animal Behaviour Science 185, 1-8.

All non-human great apes are endangered, and for these animals, captive individuals play an important role in the species’ conservation management plan. Therefore, information about their current enrichment activities is essential for maintaining a healthy...

Bozicovich, T. F. M., Moura, A. S. A. M. T., Fernandes, S. et al. 2016. Effect of environmental enrichment and composition of the social group on the behavior, welfare, and relative brain weight of growing rabbits. Applied Animal Behaviour Science 182, 72-79.

The objective of the study was to investigate if environmental enrichment and the composition of the social group would affect the behavior and relative brain weight of growing rabbits. Rabbits (72 males and 72 females)...

Zatroch, K. K., Knight, C. G., Reime, J. N. et al. 2017. Refinement of intraperitoneal injection of sodium pentobarbital for euthanasia in laboratory rats (Rattus norvegicus). BMC Veterinary Research 13, 60.

Background: The Canadian Council on Animal Care and American Veterinary Medical Association classify intraperitoneal (IP) pentobarbital as an acceptable euthanasia method in rats. However, national guidelines do not exist for a recommended dose or volume...

Schneider, B. M., Erhard, M. H., Scheipl, F. et al. 2016. Comparison of 2 gentling programs for laboratory rats: Effects on the behavior toward humans. Journal of Veterinary Behavior 12, 73-81.

Gentling can reduce the fear reactions of young laboratory rats toward people long term. We were able to show this outcome in a previous study that involved a successful but elaborate gentling program. In the...

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...

Yamanashi, Y., Matsunaga, M., Shimada, K. et al. 2016. Introducing tool-based feeders to zoo-housed chimpanzees as a cognitive challenge: Spontaneous acquisition of new types of tool use and effects on behaviours and use of space. Journal of Zoo and Aquarium Research 4(3), 147-155.

Cognitively challenging environments are vital to the welfare of captive animals. However, practical enrichment devices that can facilitate animals’ natural behaviours and accommodate individual variation are still limited. We created two types of feeders to...

Bakker, J., Ouwerling, B., Hedit, P. J. et al. 2015. Advantages and risks of housing changes to improve animal wellbeing in a breeding colony of common marmosets (Callithrix jacchus). JAALAS 54(3), 273-279.

Between 1975 and 2014, housing conditions for laboratory-housed marmosets changed dramatically after the introduction of new guidelines designed to improve their care and wellbeing. According to these guidelines, our facility provided marmosets with outside enclosures...

Boulanger Bertolus, J., Nemeth, G., Makowska, I. J. et al. 2015. Rat aversion to sevoflurane and isoflurane. Applied Animal Behaviour Science 164, 73-80.

Virtually all rodents used in research are eventually euthanized. Best practice is to anaesthetize these animals before euthanasia using a halogenated anaesthetic such as isoflurane. Exposure to isoflurane is aversive, but less so than exposure...

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...