Short and long-term effects of endogenous cortisol on personality traits and behavioral syndromes

Animals express consistent individual differences in some behaviours, termed animal personality but behaviours can also considerably vary within individuals, within minutes or hours, due to environmental stimuli. Consistent among-individual variation is often assumed to be mediated by hormonal mechanisms. Hormones are also involved in flexible and fast responses towards environmental stimuli. Even though basic mechanisms by which hormones regulate behaviours are known, much of the quantitative patterns underlying hormone-behaviour interactions within and among individuals, remain unclear. Here, we conducted two experiments to investigate the immediate, short-term effects of experimentally elevated cortisol titres on well-known animal personality traits (Experiment 1) and the potential long-term effects of such experimentally elevated cortisol titres (Experiment 2) in the medium-sized cavy (Cavia aperea). Therefore, we tested how personality traits related to stress-coping, novelty seeki..., These are the accompanying raw data to the publication: Short and long-term effects of endogenous cortisol on personality traits and behavioral syndromes.
Detailed methods can be found in the article. Compiled are raw data of two experiments. Experiment I: Data of behavioural observations under control (undisturbed) versus treatment (received a single dose of exogenous cortisol).
Experiment II: data of behavioural observations and blood plasma hormone concentrations taken 1 month (Testround 1) and 2 months (Testround 2) after the end of a three-weeks cortisol feeding experiment. Raw data were not processed in any way. , , # raw\_data\_Short and long-term effects of endogenous cortisol on personality traits and behavioral syndromes

In total, 14 adult unrelated female *Cavia aperea* were used for Experiment I and 50 (24 males, 26 females) adult animals were used for Experiment II. All animals descended from a breeding population of wild cavies kept at Bielefeld University, bred and raised under identical laboratory conditions.

In both experiments, females received 5 mg cortisol powder (Ref. Nr. 352450050; Arcos Organics) on a slice of cucumber, while males, which are on average slightly heavier than females, received 6 mg. In Exp. I, animals received a single dose of cortisol (or a control cucumber) directly followed by a behavioural test. In Exp. II, animals received either the cucumber with cortisol or the control on two out of three days for a period of 21 days and behavioural observations started two weeks after the end of the 21 days treatment period.

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