Consequences of high temperatures and premature mortality on the transcriptome and blood physiology of wild adult sockeye salmon (Oncorhynchus nerka). Oncorhynchus nerka

We collected sockeye salmon from the Fraser River, British Columbia, and held them at ecologically relevant temperatures (14C and 19C) determine the effect of elevated water temperature on cellular processes in non-lethally sampled gill tissue and blood plasma over a period of seven days that represents a significant portion of their upstream migration. Time-matched fish that died prematurely over the course of the holding study were also sampled for gill tissue and the transcriptomic responses in moribund fish were compared with surviving fish. This is the first study to experimentally examine transcriptomic responses to high water temperature and premature mortality in wild-caught Pacific salmon and the results will help in understanding some of the cellular mechanisms involved in large-scale migration mortality in Pacific salmon during warm water periods and for predicting or understanding causes of mortality in naturally senescing adult Pacific salmon. Overall design: Forty samples were analyzed on forty two-channel microarrays, using a common reference design, with multiple biological replicates for each temperature condition. Fish were further classified into survivor and moribund based on their status after 7 days in captivity.