| 1. |
- Fraser, Thomas William Kenneth, et al.
(författare)
-
Increased reactivity and monoamine dysregulation following stress in triploid Atlantic salmon (Salmo salar)
- 2015
-
Ingår i: Comparative Biochemistry and Physiology A. - : Elsevier BV. - 1095-6433 .- 1531-4332. ; 185, s. 125-131
-
Tidskriftsartikel (refereegranskat)abstract
- Artificial triploid salmonids are sterile and therefore commercially bred to prevent genetic interactions between wild and domestic fish strains. The full biological effects of having an extra chromosome set are largely unknown, but triploids are considered to be more sensitive to sub-optimal environmental conditions and to be stressed by the presence of diploid conspecifics. Brain serotonergic and dopaminergic activity are known to regulate the stress response in vertebrates, but monoamine systems in diploid and triploid fish have yet to be compared. Here we study monoamine neurochemistry in the telencephalon and brain stem of juvenile diploid and triploid Atlantic salmon (Salmo salar) in response to stress (unstressed vs stressed individuals) and holding (separate- vs mixed-ploidy) conditions. Both diploids and triploids showed an increase in serotonergic activity following stress, but the increase was significantly greater in the telencephalon of triploids compared to diploids. Furthermore, while telencephalic dopaminergic activity was significantly increased in diploids following stress, there was no response in triploids. Holding conditions had a significant effect on dopaminergic activity in the brain stem of diploids only, with lower values in mixed- compared to separate-ploidy conditions. These results suggest artificially produced triploids experience increased reactivity and monoaminergic dysregulation following stress that may impede their welfare and performance.
|
|
| 2. |
- Moltesen, Maria, et al.
(författare)
-
Cognitive appraisal of aversive stimulus differs between individuals with contrasting stress coping styles; evidences from selected rainbow trout (Oncorhynchus mykiss) strains
- 2016
-
Ingår i: Behaviour. - 0005-7959 .- 1568-539X. ; 153:13-14, s. 1567-1587
-
Tidskriftsartikel (refereegranskat)abstract
- In animals, personality variations in response to stress and energy demands have been established. Cognitive processing of negative stimuli correlates with stress response patterns. Still, the relative contribution of cognitive appraisal or physiological demands to the behavioural output needs to be clarified. In this study we utilized reactive (high-responsive, HR) and proactive (low-responsive, LR) rainbow trout strains to investigate how contrasting reactions to hypoxia are related to individual variation in metabolism and/or cognition. The HR-LR strains did not differ in standard metabolic rate or hypoxia tolerance. HR trout displayed more pronounced avoidance to a signal cue after being conditioned with hypoxia, suggesting that they experienced this stimulus more aversive than LR trout. Together with differences in forebrain c-fos activation patterns in dorsomedial pallium, these results suggest cognitive differences between the strains. These results demonstrate that differences in personality/stress coping style can be related to contrasts in cognition, which are independent of metabolic differences.
|
|
