Injections to pregnant mice produce prenatal stress that affects aggressive behavior in their adult male offspring

Maternal stress could reprogram the developing fetal nervous system. A common target of maternal glucocorticoids is fetal neuro-endocrine axis. In the present study, pregnant mice were exposed to stress by injection and their male offspring were tested for sexual and aggressive behaviors in adult life. Three groups of pregnant mice were exposed to stress by […]

Complex Environmental Enrichment and Spatial Reference Memory in Middle-Aged Mice

The effect of different forms of continuous environmental enrichment on the spatial reference memory of 22 middle-aged female CB57BL/6 mice was examined. All mice were socially housed in either standard (social enrichment only) or complex enriched (social and environmental enrichment) cages for 7 weeks. Enhanced spatial memory as tested on the Barnes Maze was observed […]

The motivation of group-housed laboratory mice to leave an enriched laboratory cage

Animals used in research are often housed in small, barren cages. Providing environmental enrichment should improve their welfare, and a consequence of this might be a reduction in the animal’s motivation to leave an enriched cage. I examined this possibility by housing laboratory mice, Mus musculus, in a cage that provided cagemates, food, water, large […]

Clustered environmental enrichments induce more aggression and stereotypic behaviour than do dispersed enrichments in female mice

Adding environmental enrichments to a previously resource-poor cage or enclosure can sometimes cause elevated aggression in socially housed animals, due to competition over the provided resources. Here, using female C57BL/6J mice, we investigated whether the way that environmental enrichments are distributed affects the risk of negative interactions between individuals and whether familiar siblings are less […]

A comparison of a manual and an automated behavioural analysis method for assessing post-operative pain in mice

Current methods of identifying and analysing behavioural signs of pain in mice are highly time consuming and labour intensive. HomeCageScan (HCS) is an automated analysis system that may offer an alternative to manual scoring. Thirty-two male mice undergoing vasectomy were filmed before and at 1h following surgery. Their behaviour was analysed by manual scoring and […]

More than numbers matter: The effect of social factors on behaviour and welfare of laboratory rodents and non-human primates☆

With the development of laboratory animal science, increasing attention has been given to the possible influence of housing and husbandry on the behaviour and welfare of laboratory animals as well as on the scientific integrity. With the present paper, we aim to contribute to this knowledge by reviewing existing literature on how social factors influence […]

Effect of feed and environmental enrichment on development of stereotypic wire-gnawing in lab mice

At 21 days of age, 16 pairs of male laboratory mice of the ICR strain were weaned and allocated to four treatment groups in a 2×2 factorial design matched for genetic background (litter) and body weight. Factor one was the hardness of the food pellets with a significant 2.5-fold difference between soft and hard feed. […]

Environmental enrichment, immunocompetence, and resistance to Babesia microti in male mice

Groups of male CFLP mice housed in cages furnished with shelves and nestboxes showed increased aggression and reduced resistance to an experimental infection of Babesia microti when compared with groups in unfurnished cages. Both a bystander measure of immunocompetence (serum total IgG concentration) and resistance to B. microti decreased as the number of attacks received […]

Variation in stress reactivity affects cage-induced stereotypies in female CD-1 (ICR) mice

Stereotypies in captive animals typically occur under conditions that are stressful for the animals, and there is some anecdotal evidence that stress levels during early stereotypy development predict later stereotypy levels. Based on this and on the involvement of stress in the behavioural sensitization to psychostimulant drugs, it has been hypothesized that stereotypy development might […]

Analyzing corticosterone metabolites in fecal samples of mice: a noninvasive technique to monitor stress hormones

In small animals like mice, the monitoring of endocrine functions over time is constrained seriously by the adverse effects of blood sampling. Therefore, noninvasive techniques to monitor, for example, stress hormones in these animals are highly demanded in laboratory as well as in field research. The aim of our study was to evaluate the biological […]