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. 
Clipperton-Allen, A. E., Ingrao, J. C., Ruggerio, L. et al. 2015. Long-term provision of environmental resources alters behavior but not physiology or neuroanatomy of male and female BALB/c and C57BL/6 mice. JAALAS 54(6), 718-30.

Few studies have evaluated the long-term effects of providing environmental resources to mice. This consideration is important given that mice are often maintained in vivaria for months. We evaluated the effects of providing simple cage...

Buijs, S., Tuyttens, F. A. M. 2015. Evaluating the effect of semi-group housing of rabbit does on their offspring's fearfulness: Can we use the open-field test? Applied Animal Behaviour Science 162, 58-66.

Breeding does are usually housed one doe per cage, but there is an increased interest in (semi-)group housing systems designed to improve welfare. However, there is a lack of information on how such systems actually...

Moody, C. M., Makowska, I. J., Weary, D. M. 2015. Testing three measures of mouse insensibility following induction with isoflurane or carbon dioxide gas for a more humane euthanasia. Applied Animal Behaviour Science 163, 183-87.

Laboratory mice are commonly killed via exposure to gradually increasing concentrations of isoflurane and carbon dioxide (CO2) gas. Once rendered insensible using isoflurane or CO2, a high concentration of CO2 is used to decrease time...

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...

Cassidy, L., Semple, S., Hannibal, D. et al. 2015. Behavioural and physiological effects of housing type on laboratory housed female rhesus macaques (Macaca mulatta). Folia Primatologica 86(4), 259-60.

Due to the despotic nature of rhesus macaques (Macaca mulatta) and their frequent use in biomedical research, it is important to understand the impact that standard housing practices can have on individuals of this species...

Molesti, S., Majolo, B. 2015. No short-term contingency between grooming and food tolerance in Barbary macaques (Macaca sylvanus). Ethology 121(4), 372-82.

The exchange of services such as allo-grooming, allo-preening, food tolerance and agonistic support has been observed in a range of species. Two proximate mechanisms have been proposed to explain the exchanges of services in animals...

Xing, G., Lu, J., Hu, M. et al. 2015. Effects of group housing on ECG assessment in conscious cynomolgus monkeys. Journal of Pharmacological and Toxicological Methods 75, 44-51.

Assessing the cardiovascular safety of new chemical or biological entities is important during pre-clinical development. Electrocardiogram (ECG) assessments in non-human primate (NHP) toxicology studies are often made using non-invasive telemetry systems. We investigated whether ECG...

Jirkof, P. 2015. Effects of experimental housing conditions on recovery of laboratory mice. Lab Animal 44(2), 65-70.

The beneficial effects of environment and social support during disease recovery in humans are widely accepted. Because laboratory mice are social animals and are highly motivated to interact with each other and with their environment...

Maher, R. L., Barbash, S. M., Lynch, D. V. et al. 2015. Group housing and nest building only slightly ameliorate the cold stress of typical housing in female C57BL/6J mice. American Journal of Physiology 308(12), R1070-R1079.

Huddling and nest building are two methods of behavioral thermoregulation used by mice under cold stress. In the laboratory, mice are typically housed at an ambient temperature (Ta) of 20°C, well below the lower end...

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...

Kaiser, R. A., Tichenor, S. D., Regalia, D. E. et al. 2015. Telemetric assessment of social and single housing: Evaluation of electrocardiographic intervals in jacketed cynomolgus monkeys. Journal of Pharmacological and Toxicological Methods 75, 38-43.

Introduction: Proactive efforts to socially house laboratory animals are a contemporary, important focus for enhancing animal welfare. Jacketing cynomolgus monkeys has been traditionally considered an exclusionary criterion for social housing based on unsubstantiated concerns that...

Buijs, S., Hermans, K., Maertens, L. et al. 2014. Effects of semi-group housing and floor type on pododermatitis, spinal deformation, and bone quality in rabbit does. Animal 8(10), 1728-1734.

The most common housing system for reproduction rabbits, individual cage housing on a wire floor, is increasingly scrutinized because of its potential detrimental impact on animal welfare. We compared three types of housing: (1) individual...

Dorman, B., Weir, D. E. 2014. From swinging single to peacefully cohabitating: A DIY way to managing rabbit socialization without breaking your budget. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 563 (Abstract #P54).

The Guide for the Care and Use of Laboratory Animals requires that all animals, without veterinary or study exemptions, be socially housed. Our current caging only allows enough floor space to house one large rabbit...

Xie, L., Zho, Q., Liu, S. et al. 2014. Effect of living conditions on biochemical and hemtalogical parameters of the cynomolgus monkey. American Journal of Primatology 76(11), 1011-1024.

The cynomolgus monkey (Macaca fascicularis) has been increasingly used in biomedical research. Although living conditions affect behavioral and physiological characteristics in macaques, little data is available on how living conditions influence blood-based parameters in the...

McGrew, K. 2014. The importance of data collection to social housing. Enrichment Record 19, 20-21.

Data collection can help facilitate the progress of social housing programs within individual institutions and in the industry as a whole. One benefit is that it provides the ability to address preconceived ideas (“myths”) with...

Rehrig, A., DiVincenti, L., Schery, L. A. 2014. Social housing of non-human primates in a research facility: socialisation across macaque species and sexes. Animal Welfare 23(4), 387-389.

Refinement of social housing practices is paramount to improving animal welfare in laboratory environments, especially with regard to non-human primates. Even though social housing of the same species should be considered the optimal paradigm, cynomolgus...

Nelsen, S. L., Bradford, D., Houghton, P. 2014. A comparison of two social housing techniques for sexually mature male cynomolgus macaques (Macaca fascicularis). American Journal of Primatology 76(S1), 104. (37th Meeting of the American Society of Primatologists Scientific Program, Abstract #208)

Social species of nonhuman primates, such as macaques, should be given the opportunity for social access to conspecifics. In captive laboratory settings, creating a system to provide this opportunity can be challenging, especially concerning sexually...

McCully, C. L., MacAllister, R. P., Smedley, J. et al. 2014. The longevity of a nonhuman primate social housing strategy: A review of group housing for rhesus male macaques maintained on active protocols in biomedical research. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 566-567 (Abstract #PS67).

Regulatory mandates promoting the psychologic wellbeing and addressing the social needs of nonhuman primates have been well described. In response to these directives, in 1992, we initially reported a successful group housing strategy for instrumented...

Rommers, J. M., Reuvekamp, B. J. F., Gunnink, H. et al. 2014. Effect of hiding places, straw and territory on aggression in group-housed rabbit does. Applied Animal Behaviour Science 157, 117-126.

Group-housing of rabbit does may be preferred from welfare point of view. However, group-housing causes agonistic behaviour which may cause severe injuries. Severe injuries may be prevented by offering hiding places for attacked does. Providing...

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...

Kalliokoski, O., Teilmann, A. C., Jacoben, K. R. et al. 2014. Do singly housed male mice get lonely? Evidence of depressive states after short-term single housing of BALB/c and C57BL/6 mice. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 597. (Abstract #P184).

Through behavioral and preference studies we know that mice prefer company. Laboratory mice should thus never be housed alone, if a viable option exists. Yet single housing is a fairly common practice, in particular with...

Gaskill, B. 2014. Aggression in laboratory mice: Potential influences and how to manage it. Enrichment Record 18, 22-25.

Aggression is a naturally occurring behavior of mice that can provide benefit to those that display it in the wild. Many factors appear to influence these negative social interactions between mice, making mitigation in the...

Baker, K. C., Coleman, K., Bloomsmith, M. A. et al. 2014. Pairing rhesus macaques (Macaca mulatta): methodology and outcomes at four national primate research centers. American Journal of Primatology 76(S1), 104. (37th Meeting of the American Society of Primatologists Scientific Program, Abstract #207)

Pairing laboratory macaques is a high priority goal for many behavioral management programs. There are numerous methodological differences in introduction procedures across facilities, including the intermediate stages used between single housing and full contact. A...

Baker, K. C., Bloomsmith, M. A., Oettinger, B. et al. 2014. Comparing options for pair housing rhesus macaques using behavioral welfare measures. American Journal of Primatology 76(1), 30-42.

In a biomedical research environment, research or management procedures may render continuous full contact pairing of rhesus macaques (Macaca mulatta) unfeasible. This study aimed to determine whether separation on a frequent basis or housing in...

Abney, D. M., Toscano, J. E., Poor, L. L. et al. 2014. Successful social housing of adult male cynomolgus macaques with similar bodyweights. American Journal of Primatology 76(S1), 86. (37th Meeting of the American Society of Primatologists Scientific Program, Abstract #151)

At Charles River Laboratories, we are committed to ensuring all animals have the highest level of care and welfare. To this end, our social housing program includes placing all nonhuman primates in pairs or groups...