Show simple item record

dc.contributor.advisorJensen, Ingvill
dc.contributor.advisorTveiten, Helge
dc.contributor.advisorJohnsen, Hanne
dc.contributor.advisorJohansen, Lill-Heidi
dc.contributor.authorAndersen, Renate
dc.date.accessioned2020-11-25T10:57:57Z
dc.date.available2020-11-25T10:57:57Z
dc.date.issued2015-11-25
dc.description.abstractExposure to stress may have a profound impact on the physiology and health of an individual later in life. During a production cycle of Atlantic salmon eggs, the eggs are subjected to different kind of handling, e.g. shocking and transport. Handling of this extent would have elicited stress responses in adult fish. Stress responses can broadly be divided into primary, secondary and tertiary response. The primary stress response consists of two pathways where one of them, the hypothalamus-pituitary-interrenal (HPI) axis, results in elevations of circulating corticosteroids. On a cellular level, heat shock proteins (HSP) play an important role as a secondary response. In embryos, cortisol, which is the main corticosteroid in teleosts, is not synthesized before around hatching. However, genes that are central in the HPI-axis and HSP genes have been detected in fish embryos at several developmental stages. Even though the HPI-axis is not fully developed a stressor may alter the gene expressions. Based on this, eight genes central in the HPI-axis (crf1, crf2, pomcA1, pomcA2, pomcB, gr1, gr2 and mr) and two HSP genes (hsp70a and hsp90a4) were examined, in Atlantic salmon embryos subjected to shocking and transport. In addition, newly hatched larvae, and larvae at start feeding subjected to a stress challenge, were analysed to map the ontogeny of the genes, and to examine any possible long-term effects of the shocking and transport. Relative gene expression of whole-animal were analysed using reverse transcriptase real time polymerase chain reaction (RT-qPCR). The results showed that all genes were present in all samples examined throughout the development. The HPI-axis genes showed an increased relative expression level during development, except for gr1 and gr2 that showed a delayed increase probably due to maternal transfer. The HSP genes, however, had a low expression level at start feeding compared embryos and newly hatched larvae. The relative expression of the HPI-axis genes did not show any specific short-term or long-term differences in relative gene expression after exposure to shocking and/or transport. The HSP genes, however, showed an acute upregulation after transport, but no long-term effects. The results of this study indicates that shocking and transport are not high enough stressors to alter the expression of the HPI-axis genes. They also indicate that the HSP genes may play an important role in cellular stress response during development.en_US
dc.identifier.urihttps://hdl.handle.net/10037/19919
dc.language.isoengen_US
dc.publisherUiT The Arctic University of Norwayen_US
dc.publisherUiT Norges arktiske universiteten_US
dc.rights.accessRightsopenAccessen_US
dc.rights.holderCopyright 2015 The Author(s)
dc.subject.courseIDBIO-3955
dc.subjectembryo, salmon, stress, HPI-axisen_US
dc.subjectVDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Fish health: 923en_US
dc.subjectVDP::Landbruks- og Fiskerifag: 900::Fiskerifag: 920::Fiskehelse: 923en_US
dc.subjectVDP::Mathematics and natural science: 400::Basic biosciences: 470::Molecular biology: 473en_US
dc.subjectVDP::Matematikk og Naturvitenskap: 400::Basale biofag: 470::Molekylærbiologi: 473en_US
dc.subjectVDP::Mathematics and natural science: 400::Basic biosciences: 470::Genetics and genomics: 474en_US
dc.subjectVDP::Matematikk og Naturvitenskap: 400::Basale biofag: 470::Genetikk og genomikk: 474en_US
dc.titleHPI-axis and heat shock protein (HSP) gene transcripts, and their responsiveness to stress in Atlantic salmon (Salmo salar L.) embryos and larvaeen_US
dc.typeMaster thesisen_US
dc.typeMastergradsoppgaveen_US


File(s) in this item

Thumbnail
Thumbnail

This item appears in the following collection(s)

Show simple item record