Comparison of lipid content and fatty acid composition in muscle and liverof two notothenioid fishes from Admiralty Bay (Antarctica): an eco-physiological perspective

During Antarctic summer, total lipids (g/100 g dry matter) in Notothenia co riiceps (n = 18) and Lepido-notothen nudifrons (n = 10) were low (6.1 and 4 .7 in muscle), which is typical of Antarctic benthic species. The liver of female N. coriiceps was heavier and contained more lipids per dry weight th an the liver of males. The fatty acid composition of N. coriiceps and L. nu difrons was dominated by polyunsaturated fatty acids (PUFA, respectively, 4 4 and 49% of total fatty acids in muscle, 31 and 46% in liver), which inclu ded primarily C20:5n-3 (18 and 19% in muscle, 13 and 18% in liver) and C22: 6n-3 (15 and 19% in muscle, 12 and 20% in liver). In L. nudifrons, the leve ls of some unsaturated fatty acids increased with age and size. The high pe rcent unsaturation (PUFA + MUFA, 78 and 80% in muscle, 82 and 80% in liver) is a response to low water temperature (-0.4 degreesC). Fish fatty acid pr ofiles reflect fatty acid profiles of the diet (amphipods, macroalgae and f ish).