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. 

Group housing of socially-deprived individuals facilitates welfare and socialisation of primates. Here, we studied behavioural and hormonal changes in the course of group formation among nine male chimpanzees, Pan troglodytes. Aggression, reassurance, and grooming were...

Previous studies have shown that loneliness increases the risk of AD (Alzheimer’s disease) onset, while active and frequent social housing delays the onset of cognitive impairment. The mechanism of how this occurs remains unclear. In...

The AVMA Guidelines for the Euthanasia of Animals considers injection of barbiturates to be an acceptable method of euthanasia in rodents but states there is a potential for pain when administered intraperitoneally. This study examined...

There are different husbandry situations that lead to social isolation of male mice. Besides legal considerations, single housing has a negative impact on behavioural and molecular studies. We have implemented two strategies, the ‘companion mouse’...

Those who have worked with C57BL/6 males know how aggressive they can be towards their cage mates. We poured over academic journals, reading every article we could find regarding male home cage aggression. Three articles...

Burrowing and nest building are examples of highly motivated innate behaviours in rodents. Assessments based on these behaviours can be used as non-invasive indicators of pain, distress and suffering. In this study, we investigated the...

Aggression in group-housed laboratory mice is a serious animal welfare concern. Further understanding of the causes of mouse aggression could have a significant impact on a large number of laboratory animals. The NC3Rs led a...

Due to primate adaptations for sociality, captive rhesus macaques have optimal welfare and utility as a biomedical model when they can be maintained in outdoor social groups. As a despotic species; however, aggression can result...

The mouse is the most commonly used mammal in scientific research, and housed in research facilities around the world. Mice are a social species, but when housing male mice together in a confined environment in...

Different aspects of sociality bear considerable weight on the individual- and group-level welfare of captive nonhuman primates. Social Network Analysis (SNA) is a useful tool for gaining a holistic understanding of the dynamic social relationships...

Because tetanus can cause significant morbidity and mortality in NHP, colonywide vaccination with tetanus toxoid is recommended for outdoor breeding colonies of rhesus macaques, with primary immunizations commonly given to infants at 6 mo of...

Laboratory rhesus macaques are often housed in pairs and may be temporarily or permanently separated for research, health, or management reasons. While both long‐term social separations and introductions can stimulate a stress response that impacts...

Understanding how social relationships affect long-term stress is important because stress has a profound impact on the welfare of animals and social relationships often exert a strong influence on their stress responses. The purpose of...

Surgical implantation of tumour pieces has been used regularly in the passage of tumour models. This involves an invasive surgical procedure, carried out under anaesthesia, ensuring mice have adequate pain relief and peri-operative care. The...

"When you keep adult Rhesus macaque (Macaca mulatta) males, adult Cynomolgus (Macaca fascicularis) males or adult Vervet males (Chlorocebus pygerythrus), in the same enclosure, is it advisable to have the canines of the males blunted...

The aim of the present review is to discuss how housing conditions affect behavioral performance in laboratory rodents from an ethological view. Commonly used laboratory rodents such as rats and mice, are originally captured animals...

Social separation is an increasingly used strategy to experimentally assess psychogenic stress in nonhuman primates, yet it is also inherently required for captive management. Surprisingly, little is known on the effects of an individual left...

Play is sometimes considered as an indicator of positive animal welfare. However, it is not yet sufficiently understood whether or not social play among adults can be considered as such an indicator because it is...

We studied how space allowance affects measures of animal welfare in mice by systematically varying group size and cage type across three levels each in both males and females of two strains of mice (C57BL/6ByJ...

At Charles River, we are committed to ensuring all animals have the highest level of care and welfare. For juvenile, subadult and adult female cynomolgus macaques (Macaca fascicularis), we have a near 100% success rate...

Identification of behaviors early in the process of rhesus macaque social introductions that might predict social housing success would allow primate managers to best allocate resources and minimize animal stress by aborting introductions unlikely to...

Limiting contact aggression and social stress is a principal animal welfare challenge in managing large groups of captive nonhuman primates. This challenge is especially pronounced in rhesus monkeys (macaca mulatta), a species characterized by a...

Socialization is one of the most important forms of enrichment for rhesus macaques. However, pair introductions can result in aggression and injury if partners are incompatible, even days after the initial introduction. Identifying predictors of...

Previous observational research of captive rhesus macaques suggests that higher coefficients of relatedness within matrilines are associated with lower rates of severe within‐matriline aggression and more cohesive grooming communities. We tested whether experimental removals targeted...

Group living in primates may impact the risk of pathogen acquisition in two ways. First, social connectedness makes individuals more susceptible to pathogens via contact‐mediated transmission. Yet in strongly bonded societies, having close connections and...