Differences in stress reactivity between zebrafish with alternative stress coping styles

Abstract

Animals experience stress in a variety of contexts and the behavioural and neuroendocrine responses to stress can vary among conspecifics. The responses across stressors often covary within an individual and are consistently different between individuals, which represent distinct stress coping styles (e.g. proactive and reactive). While studies have identified differences in peak glucocorticoid levels, less is known about how cortisol levels differ between stress coping styles at other time points of the glucocorticoid stress response. Here we quantified whole-body cortisol levels and stress-related behaviours (e.g. depth preference, movement) at time points representing the rise and recovery periods of the stress response in zebrafish lines selectively bred to display the proactive and reactive coping style. We found that cortisol levels and stress behaviours are significantly different between the lines, sexes and time points. Further, individuals from the reactive line showed significantly higher cortisol levels during the rising phase of the stress response compared with those from the proactive line. We also observed a significant correlation between individual variation of cortisol levels and depth preference but only in the reactive line. Our results show that differences in cortisol levels between the alternative stress coping styles extend to the rising phase of the endocrine stress response and that cortisol levels may explain variation in depth preferences in the reactive line. Differences in the timing and duration of cortisol levels may influence immediate behavioural displays and longer lasting neuromolecular mechanisms that modulate future responses.

Differential effects of ethanol on behavior and GABAAreceptor subunit expression in zebrafish (Danio rerio) with alternative stress coping styles

“…In this study, we used the high-stationary behavior (HSB) and low-stationary behavior (LSB) lines of zebrafish ( Danio rerio ). These two lines exhibit differences in stress-related behaviors across multiple behavioral assays, learning and memory, glucocorticoid responses, neurotranscriptome profiles, and morphology consistent with the reactive and proactive stress coping styles 5,6,10,12,45,47,49,50 . Therefore, we consider any fish from the HSB or LSB lines to have the reactive or proactive stress coping style, respectively.…”

“…Following the 14 th day of treatment, fish were exposed to a novelty stressor by placing them into the Novel Tank Diving Test (NTDT) assay following established procedures 5,10,49 . Reduced transitions to and time spent in the top half of the tank are indicators of heightened stress and anxiety 5,24,51 .…”

“…Across many taxa there exists two alternative correlated suites of behavioral and physiological responses to stressors known as the proactive and reactive stress coping styles 2,3,5–7 . Proactive individuals actively engage stressors and characteristically exhibit a lower whole-body cortisol response compared to reactive individuals in response to novelty 2,3,5,8–10 . Additionally, proactive and reactive individuals differ in expression of key neurotransmitter receptors related to stress and anxiety, such as serotonin, dopamine, and GABA (γ-amino butyric acid) receptors 2,3,11,12 .…”

The impact of personality, morphotype and shore height on temperature‐mediated behavioural responses in the beadlet anemone Actinia equina

“…Low‐shore individuals, which are immersed for longer periods of the day, may have more environmental scope to up‐regulate this response. They may also be less acclimated to temperature fluctuations (Chapperon et al., 2016) and therefore be more stressed at high temperatures (Abram et al., 2017), leading them to be more risk‐averse or physiologically unprepared in the face of further stressors (Koolhaas et al., 2010; Wong et al., 2019).…”

“…Personality variation is linked with how individuals respond to environmental stressors both behaviourally and physiologically (Koolhaas, de Boer, Coppens, & Buwalda, 2010) and divergence in these responses to environmental challenge (e.g. Dong et al., 2008; Wong, French, & Russ, 2019) could cause varied fitness levels in the face of environmental perturbation (Killen, Adriaenssens, Marras, Claireaux, & Cooke, 2016). Investigating the effects of environmental change on personality variation can therefore contribute to our understanding of how different populations, and individuals within those populations, are likely to cope with anthropogenic climate change (Tuomainen & Candolin, 2011).…”