In the present study, we investigated the year-round variability in the expression of fads2 (measured via quantitative real-time PCR) in the liver of the European perch in a boreal lake in relation to individual variation in size, sex, and maturity. Our objectives were to (i) assess if there were any seasonal changes in the expression of fads2 in the liver of P. fluviatilis and (ii) if these changes could be related to environmental (seasonality in temperature, light, oxygen) or biological variation (body size, sex, maturity, diet). To answer these questions, together with fads2 activity we report carbon stable isotopes values as well as the content of fatty acids (FAs) in perch tissues (liver, muscle and gonad) and potential perch prey items sampled simultaneously.

2022