How Does Temperature Affect Primary Barrier Functions in Atlantic Salmon (Salmo Salar L.) Post‐Smolts?

Abstract

Environmental temperature has a considerate impact over near all aspects of physiology in both wild and cultured salmonids. In addition to climate change, insight regarding the effects of temperature over physiology is crucial for the aquaculture sector, as temperature differences during the seaward transfer of fish from (semi‐) closed containment systems to open sea pens may be great and ultimately dependent on the prevailing season. For example, transferring of fish will likely occur towards higher temperatures during the summer months and lower temperatures during winter months. Further, open‐pen rearing of post‐smolt salmonids occur throughout the year at varying seasonal temperatures. Due to these temperature differences, it is therefore important to know how temperature influences tissue characteristics and modulates physiological functioning and adaptation, which processes maybe challenged during stress, thereby contributing to the stress response and overall robustness of the fish. Here we present how differences in temperature, ranging from 4°C to 18°C, affects Atlantic salmon (Salmo salar L.) post‐smolt primary barrier composition and functioning of osmoregulation in seawater. Our results suggest that primary barrier characteristics change with shifting temperatures, resulting in new physiological set points to match osmoregulatory demand in those conditions. Further, we elucidate how prior acclimation history affects the capacity of these barrier systems to respond when confronted by an additional acute stress. In this study, we investigated key changes in gill and skin phospholipid (PL) and fatty acid (FA) compositions utilizing electrospray ionization‐tandem mass spectrometry (ESI‐MS/MS) and gas chromatography (GC‐FID), in concert with qPCR expression profile changes of vital genes involved in osmoregulation, thereby aiming to understand how these correlate to changing patterns in primary barrier performance at different temperatures.Support or Funding InformationCenter for Research Based Innovation, “CtrlAqua” Project Number 237856/030This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.