A spatial judgement task to determine background emotional state in laboratory rats, Rattus norvegicus

Humans experiencing different background emotional states display contrasting cognitive (e.g. judgement) biases when responding to ambiguous stimuli. We have proposed that such biases may be used as indicators of animal emotional state. Here, we used a spatial judgement task, in which animals were trained to expect food in one location and not another, to determine […]

Removing individual rats affects indicators of welfare in the remaining group members

The removal of individuals from social groups, e.g. in order to maintain appropriate stocking densities in groups of rapidly growing young laboratory rats, is often necessary. However, such removals may be stressful and few studies have investigated their effects on the behaviour, physiology and welfare of the remaining group members. In this study we investigated […]

The effects of intrusion on the behaviour of caged laboratory rats (Rattus norvegicus): Consequences for welfare

This experiment examines the consequences and welfare implications of the introduction of new rats to established (resident) caged laboratory rat groups. The effects on investigatory and aggressive behaviours of the established and the newly introduced rats were measured. The aggressive status within each established resident group was known prior to the introduction; the status of […]

Disruptive effects of standard husbandry practice on laboratory rat social discrimination

Elements of husbandry procedures, such as handling, may disrupt rodent social behaviour. Such effects may be contingent upon the familiarity between individuals and upon the quality and quantity of the disruption. We investigated this issue using laboratory rats. We placed 36 rats into groups of three. At the point of group formation, and at 24 […]

Effects of physical activity and group size on animal welfare in laboratory rats

The aim of this study was to investigate whether moderate physical activity and group size influence physical fitness, the level of social interactions in the home cage and rats’ performance in the Elevated Plus Maze and a handling test. Forty-eight male Sprague Dawley rats were kept in groups of two, four or eight for seven […]

The effects of enhancing cage complexity on the behaviour and welfare of laboratory rats

This experiment was carried out to investigate the long-term effects of enhancing cage complexity on behavioural measures of welfare in laboratory rats. We housed 72 rats in groups of four in either ‘enriched’ or ‘unenriched’ cages for six weeks. Scan and focal animal sampling were conducted in both the light and dark phase of the […]