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- Schjolden, Joachim, et al.
(författare)
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Divergence in behavioural responses to stress in two strains of rainbow trout (Oncorhynchus mykiss) with contrasting stress responsiveness
- 2005
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Ingår i: Hormones and Behavior. - : Elsevier BV. - 0018-506X .- 1095-6867. ; 48:5, s. 537-544
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to establish whether two lines of rainbow trout divergent for their plasma cortisol response to a standardized stressor would show consistent differences in their behavioural response to a range of challenging situations. Our results show that the high- and low-responding (HR and LR) lines of rainbow trout did not differ in the aggression shown towards an intruder or in their response to the introduction of a novel object to their home environment. However, there was a difference in behaviour between the two selection lines when they were exposed to two unfamiliar environments. These results suggest that the behaviour of the HR and LR fish differs when they are challenged in unfamiliar environments, while their behaviour does not differ when they are challenged in their home environment. These observations are in agreement with studies on mammals that show that individuals with reactive coping styles perform similarly to proactive animals when they are challenged in a familiar environment, while they show different behaviour when they are challenged in unfamiliar environments. Thus, these results provide further evidence that the HR and LR selection lines of rainbow trout exemplify the two different coping styles described in mammals.
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| 3. |
- Bell, Alison M., et al.
(författare)
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Variable neuroendocrine responses to ecologically-relevant challenges in sticklebacks
- 2007
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Ingår i: Physiology and Behavior. - : Elsevier BV. - 0031-9384 .- 1873-507X. ; 91:1, s. 15-25
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Tidskriftsartikel (refereegranskat)abstract
- Variable neuroendocrine responses to ecologically-relevant challenges in sticklebacks. PHYSIOL BEHAV 00(0) 000-000, 2006. Here, we compare the behavioral, endocrine and neuroendocrine responses of individual sticklebacks exposed to either an unfamiliar conspecific or to a predator. We found that the two stressors elicited a similar hypothalamic–pituitary–interrenal response as assessed by whole-body concentrations of cortisol, but produced quite different patterns of change in brain monoamine and monoamine metabolite content as assessed by concentrations of serotonin (5-HT), dopamine (DA), norepinephrine (NE) and the monoamine metabolites 5-hydroxyindole acetic acid (5-HIAA), homovanillic acid (HVA) and 3-4-dihydroxyphenylacetic acid (DOPAC). For example, relative to baseline levels, NE levels were elevated in individuals exposed to a predator but were lower in individuals confronted by a challenging conspecific. Levels of monoamine neurotransmitters in specific regions of the brain showed extremely close links with behavioral characteristics. Frequency of attacking a conspecific and inspecting a predator were both positively correlated with concentrations of NE. However, whereas serotonin was negatively correlated with frequency of attacking a conspecific, it was positively associated with predator inspection. The data indicate that the qualitative and quantitative nature of the neuroendocrine stress response of sticklebacks varies according to the nature of the stressor, and that interindividual variation in behavioural responses to challenge are reflected by neuroendocrine differences.
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