Prenatal stress in farmed salmon: Consequences for emotional and cognitive function in offspring

Ane Skjelfjord

It is known that prenatal stress influences the physiological and morphological development of offspring negatively - but how does it affect their behavioural development?

Prosjektleder: Bjarne O. Braastad
Post doc: Marit Skog Eriksen

Physiological and morphological effects of maternal cortisol in fish
We have previously shown in farmed salmon that augmented levels of maternal cortisol exert detrimental impacts on the physiological and morphological development of offspring. Our results thus accentuate the importance of knowledge on how the maternal endocrinological state during gametogenesis may impinge on offspring characters in salmonids, and further substantiates the necessity of incorporating maternal effects when evaluating rearing conditions and animal welfare in commercial aquaculture. There is however a huge lack of information regarding the impacts of prenatal stress on behavioural dispositions in fish.

How may prenatal stress affect fish offspring's behaviour?
In mammals and birds, prenatally stressed offspring typically have reduced stress coping ability, demonstrated by a general propensity to be more fearful and exhibit exaggerated behavioural responses to novel and aversive situations; and they may also show impaired competitive ability and learning skills. In the current project we will give mature females intraperitoneal cortisol implants in order to investigate whether (modelled) prenatal stress in farmed salmon affects the emotional and cognitive function of offspring, and thereby their capacity to cope with stress. Specifically, we will test the hypothesis that prenatal stress increases fearfulness and stress reactivity by exposing offspring to a novel environment.

The impacts of prenatal stress on competitive ability will be measured by pairing prenatally stressed offspring and controls and observing social dominance. Further, the outcome of prenatal stress on cognitive skills of offspring will be investigated by assessing the number of trials needed to learn a simple conditioned task. We will also examine proximate mechanisms possibly related to the observed impacts of prenatal stress on behaviour, that is basal and stress-induced levels of cortisol, noradrenaline, serotonin and dopamine. Finally, impacts of prenatal stress on the morphology of offspring will be scrutinized.

Forskdok key words: fish, salmon, stress, behaviour, fearfulness, learning skills, competitive ability, cortisol, commercial aquaculture, ethology, animal welfare

Forskdok emneord: fisk, laks, stress, atferd, adferd, frykt, læreevne, konkurransedyktighet, kortisol, oppdrett, etologi, dyrevelferd

Oppdatert: 03.08.06
Utskriftsvennlig versjon : Arkiv : Tips en venn