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. 
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...

McCrossin, F. G. 2014. The effect of pair housing on the aye-aye (Daubentonia madagascariensis). American Journal of Primatology 76(S1), 54. (37th Meeting of the American Society of Primatologists Scientific Program, Abstract #52)

Aye-ayes (Daubentonia madagascariensis) are thought to be solitary animals and are often housed alone in captivity. However, for all primates sociality is known to play a major role in psychological well-being. Captive animals can develop...

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...

Lutz, C. K., Williams, P. C., Sharp, R. M. 2014. Abnormal behavior and associated risk factors in captive baboons (Papio hamadryas spp.). American Journal of Primatology 76(4), 355-361.

Abnormal behavior, ranging from motor stereotypies to self‐injurious behavior, has been documented in captive nonhuman primates, with risk factors including nursery rearing, single housing, and veterinary procedures. Much of this research has focused on macaque...

Crast, J., Bloomsmith, M. A., Perlman, J. E. et al. 2014. Abnormal behaviour in captive sooty mangabeys. Animal Welfare 23(2), 167-177.

The influence of several factors on abnormal behaviour was investigated in 46 singly housed sooty mangabeys (Cercocebus atys) (eight nursery-reared, 38 mother-reared), including self-injurious, self-directed, stereotypic locomotion, and faeces/urine-related behaviours (SIB, SDB, SL, FUR, respectively)...

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...

Croney, C. 2014. Let's stay together: Implications of social housing for laboratory pig welfare and management. Enrichment Record 19, 14-19.

Appropriately accommodating the pig's normal social behavior is an essential step in protecting its well-being in managed environments. Doing so is particularly important in laboratory settings in which distress due to social isolation and other...

Bayne, K. 2014. A historical perspective on social housing. Enrichment Record 18, 8-11.

The ever-broadening scope of social housing of research animals is increasingly encompassing the diversity of species used in research, including dogs, cats, rabbits, a variety of rodent species, agricultural animals, aquatic animals, and others.The Guide's...

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...

Abney, D. M., Harding, K., Toscano, J. et al. 2014. Successful social housing of mature male cynomolgus macaques in mixed sex rooms. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 567. (Abstract #P70).

We are committed to ensuring all our animals have the highest level of care and welfare. To this end, our social housing program includes placing all animals in pairs or groups. We have a rate...

Zhou, Q., Sun, Q., Wang, G. et al. 2014. Group housing during gestation affects the behaviour of sows and physiological indices of offspring at weaning. Animal 8(7), 1162-1169.

To compare the behaviour of sows and the physiological indices of their offspring in stall and group-housing systems, 28 sows were randomly distributed into two systems with 16 sows in stalls, and the other 12...

Doulames, V., Lee, S., Shea, T. B. 2014. Environmental enrichment and social interaction improve cognitive function and decrease reactive oxidative species in normal adult mice. International Journal of Neuroscience 124(5), 369-376.

Environmental stimulation and increased social interactions stimulate cognitive performance, while decrease in these parameters can exacerbate cognitive decline as a function of illness, injury, or age. We examined the impact of environmental stimulation and social...

Greenberg, G. D., Howerton, C. L., Trainor, B. C. 2014. Fighting in the home cage: Agonistic encounters and effects on neurobiological markers within the social decision-making network of house mice (Mus musculus). Neuroscience Letters 566, 151-155.

Inbred strains of mice, such as C57Bl/6, have become preferred animal models for neurobehavioral studies. A main goal in creating inbred lines is to reduce the effects of individual genetic variation on observed phenotypes. Most...

Grippo, A. J., Ihm, E., Wardwell, J. et al. 2014. The effects of environmental enrichment on depressive and anxiety-relevant behaviors in socially isolated prairie voles. Psychosomatic Medicine 76(4), 277-284.

Social isolation is associated with depression, anxiety and negative health outcomes. Environmental enrichment, including environmental and cognitive stimulation with inanimate objects and opportunities for physical exercise, may be an effective strategy to include in treatment...

Hori, M., Yamada, K., Ohnishi, J. et al. 2014. Tickling during adolescence alters fear-related and cognitive behaviors in rats after prolonged isolation. Physiology & Behavior 131, 62-67.

Social interactions during adolescence are important especially for neuronal development and behavior. We recently showed that positive emotions induced by repeated tickling could modulate fear-related behaviors and sympatho-adrenal stress responses. In the present study, we...

Krügel, U., Fischer, J., Bauer, K. et al. 2014. The impact of social isolation on immunological parameters in rats. Archives of Toxicology 88(3), 853-855.

In various toxicological studies, single housing of rodents is preferred to standardize for regulatory purposes. However, housing conditions can have severe, often underestimated, impact on results in toxicological examinations. As different husbandry conditions have been...

Kulesskaya, N., Karpova, N. N., Ma, L. et al. 2014. Mixed housing with DBA/2 mice induces stress in C57BL/6 mice: Implications for interventions based on social enrichment. Frontiers in Behavioral Neuroscience 8, 257.

Several behavioral interventions, based on social enrichment and observational learning are applied in treatment of neuropsychiatric disorders. However, the mechanism of such modulatory effect and the safety of applied methods on individuals involved in social...

Monteiro, B. M., Moreira, F. A., Massensini, A. R. et al. 2014. Enriched environment increases neurogenesis and improves social memory persistence in socially isolated adult mice. Hippocampus 24(2), 239-248.

Social memory consists of the information necessary to identify and recognize cospecifics and is essential to many forms of social interaction. Social memory persistence is strongly modulated by the animal's experiences. We have shown in...

Sharp, J., Azar, T., Lawson, D. 2014. Effects of a complex housing environment on heart rate and blood pressure of rats at rest and after stressful challenges. JAALAS 53(1), 52-60.

Housing enrichment for rodents continues to be a discussion topic within the animal care community. The objective of this study was to determine the extent to which a complex housing environment affects heart rate, blood...

Turner, P. V., Sunohara-Neilson, J., Ovari, J. et al. 2014. Effects of single compared with pair housing on hypothalamic-pituitary-adrenal axis activation and low-dose heroin place conditioning in adult male Sprague-Dawley rats. JAALAS 53(2), 161-167.

Whether social isolation of adult rats under standard laboratory conditions produces significant long-term alterations in behavior and physiology is unclear. In the present study, male Sprague–Dawley rats were singly or paired-housed for 10 wk. During...