| 2. |
- Fraser, Thomas William Kenneth, et al.
(författare)
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Increased reactivity and monoamine dysregulation following stress in triploid Atlantic salmon (Salmo salar)
- 2015
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Ingår i: Comparative Biochemistry and Physiology A. - : Elsevier BV. - 1095-6433 .- 1531-4332. ; 185, s. 125-131
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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.
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| 3. |
- Meager, Justin J., et al.
(författare)
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Multidimensionality of behavioural phenotypes in Atlantic cod, Gadus morhua
- 2012
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Ingår i: Physiology and Behavior. - : Elsevier BV. - 0031-9384 .- 1873-507X. ; 106:4, s. 462-470
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Tidskriftsartikel (refereegranskat)abstract
- Much of the inter-individual variation observed in animal behaviour is now attributed to the existence of behavioural phenotypes or animal personalities. Such phenotypes may be fundamental to fisheries and aquaculture, yet there have been few detailed studies of this phenomenon in exploited marine animals. We investigated the behavioural and neuroendocrine responses of Atlantic cod (Gad us morhua L), to situations reflecting critical ecological challenges: predator attacks and territorial challenges. Both hatchery-reared and wild fish were tested and behavioural profiles were compared with baseline conditions. We then used an objective, multivariate approach, rather than assigning individuals along one-dimensional behavioural axes, to examine whether distinct behavioural phenotypes were present. Our results indicate that two distinct behavioural phenotypes were evident in fish from each background. In hatchery-reared fish, phenotypes displayed divergent locomotor activity, sheltering, brain monoamine concentrations and responses to competitive challenges. In wild fish, phenotypes were distinguished primarily by locomotor activity, sheltering and responsiveness to predator stimuli. Hatcheries presumably represent a more stressful social environment, and social behaviour and neuroendocrine responses were important in discerning behavioural phenotypes in hatchery fish, whereas antipredator responses were important in discerning phenotypes in wild fish that have previously encountered predators. In both fish types, behavioural and physiological traits that classified individuals into phenotypes were not the same as those that were correlated across situations These results highlight the multidimensionality of animal personalities, and that the processes that regulate one suite of behavioural traits may be very different to the processes that regulate other behaviours.
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