Environmental enrichment enhances spatial cognition in rats by reducing thigmotaxis (wall hugging) during testing

Rats, Rattus norvegicus, housed with [`]environmental enrichment’ do better in tests of spatial cognition than rats housed in barren cages. The leading hypothesis is that exposure to [`]social and inanimate complexity’ leads to better cognitive-processing abilities, which directly enhances performance in a spatial task. However, enrichment is associated with reduced stress responses and anxiety in […]

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 […]

Sex differences, or not, in spatial cognition in albino rats: acute stress is the key

Male rats, Rattus norvegicus, typically outperform females in tests of spatial cognition. However, as stress affects cognition differently in the two sexes, performance differences may be an artefact of stress. Rats face at least two sources of stress during an experiment: the test situation (acute) and housing conditions (chronic, e.g. isolation). We used a task […]

Effectiveness of familiar kin and unfamiliar nonkin demonstrator rats in altering food choices of their observers

In a series of three experiments, we examined the prediction from formal theories of the evolution of social learning that, all else being equal, animals should be more likely to learn socially from familiar individuals or kin than from unfamiliar individuals or nonkin. In all three experiments, contrary to prediction, naïve Norway rats, Rattus norvegicus, […]

Sex influences rat personality more than geographical origin

The Norway rat is an indispensable model organism. Behavioral studies on rats usually concentrate on a single trait without considering how different behaviors are linked to each other and whether there are differences in this respect between rat strains or sexes. This study aims to describe the personality structure of the Norway rat, and investigate […]

Housing and Welfare in Laboratory Rats: The Welfare Implications of Social Isolation and Social Contact Among Females

Female laboratory rats (Rattus norvegicus: Wistar, Alderley Park) were housed as singletons or groups of three in units of two cages. Units were divided by different types of barrier which allowed varying degrees of social contact across the barrier. Singletons were established either with another singleton on the other side of the barrier or with […]

Auditory Categorization of Complex Sounds by Rats (Rattus norvegicus)

Little research has explored the auditory categorization abilities of mammals. To better understand these processes, the authors tested the abilities of rats (Rattus norvegicus) to categorize multidimensional acoustic stimuli by using a classic category-learning task developed by R. N. Shepard, C. I. Hovland, and H. M. Jenkins (1961). Rats proved to be able to categorize […]

Enrichment of laboratory caging for rats- a review

Rats are a well-understood and widely used laboratory species that should be provided with environmentally enriched caging in line with modern animal welfare guidelines. This paper reviews which sources of enrichment are effective and should be prioritised, and how methods for providing enrichment might be selected using rats’ preferences as a guide. Rats demonstrate high […]

Do horses with poor welfare show ‘pessimistic’ cognitive biases?

This field study tested the hypothesis that domestic horses living under putatively challenging-to-welfare conditions (for example involving social, spatial, feeding constraints) would present signs of poor welfare and cooccurring pessimistic judgement biases. Our subjects were 34 horses who had been housed for over 3 years in either restricted riding school situations (e.g. kept in single […]