Lipid dynamics in early life stages of the icefish Chionodraco hamatus in the Dumont d'Urville Sea (East Antarctica)

摘要

Lipids play a crucial role in polar regions and are of particular importance in early life stages of Antarctic fish. This work presents the significance of lipids and fatty acids (FAs) in the early life stages of the icefish Chionodraco hamatus. Analysis of lipid classes (polar lipids, PL; cholesterol, Chol; and triacylglycerol, TAG) suggested different energy allocation strategies in preflexion (< 25 mm) and postflexion larvae (> 25 mm). Structural PL dominated lipid dynamics for preflexion larvae, indicating that small individuals allocate the majority of energy toward somatic growth. Conversely, postflexion larvae appear able to switch between growth (contribution of PL) and energy storage (contribution of TAG) strategies. The condition index ratio TAG/Chol varied from 0.2 to < 2 with no differences between the two larval stages. Further, FA composition of the TAG and PL fractions suggests that both developmental stages share the same carnivorous diet and that C. hamatus relies on a few key prey items.