Metabolic changes of notothenioid fish in relation to nutritional status

Individuals of Trematomus bernacchii and Pagothenia borchgrevinki were captured and used in an experiment to understand metabolic changes, especially pertaining to the lipid transport system (lipoproteins) used, in relation to the nutritional status of the fish. Captured fish were not fed for 12 days to clear the stomach. From each species, n=7 were euthanised following oxygen consumption measurements, and blood and tissues harvested at time 00 as a pre-feeding control. The rest were hand fed for 3 days twice a day to ensure they had all eaten. Another 7 were used in oxygen consumption measurements and killed at time 0 for post feeding control. A further 7 fish were processed 1 day post end of feeding, 2 days, 3 days, 7 days, 14 days and 28 days. The stomach contents of all fish were examined. Plasma was analysed using electrophoresis to look for changes in blood proteins (especially lipoproteins) from a fed to starved state. Tissues were collected for subsequent analysis of metabolic changes in gene expression and enzyme activity.