RESUMO
Fatty acids from the several lipid classes of selected steelhead trout (Salmo gairdnerii) parr and smolt tissues, previously separated by thin-layer chromatography, were analyzed by gas-liquid chromatography. The fatty acid composition of the parr was markedly different from that of the smolt; the former being characterized by relatively low amounts of polyunsaturated fatty acids and relatively high amounts of linoleic acid, much like the typical freshwater lipid pattern. The fatty acid composition of the smolt was characterized by large proportions of long-chain polyunsaturated fatty acids. Generally, the fatty acid composition of the smolt resembled the typical seawater lipid pattern. The change in fatty acid composition of the smolt is anticipatory to seawater entry and is independent of diet and water temperature. These alterations suggest that the assumption of a polyunsaturated lipid pattern during parr-smolt transformation (smoltification) is preadaptive to seawater entry.
Assuntos
Ácidos Graxos/análise , Salmonidae/crescimento & desenvolvimento , Truta/crescimento & desenvolvimento , Aclimatação , Tecido Adiposo/análise , Animais , Cromatografia Gasosa/métodos , Ácidos Graxos Insaturados/análise , Água Doce , Lipídeos/análise , Músculos/análise , Estações do Ano , Água do Mar , Distribuição TecidualRESUMO
1. Wax esters were identified in the serum and liver of steelhead trout. 2. Confirmation of the identity was made by thin-layer chromatography of the wax ester hydrolysis products: long chain alcohols and fatty acids. 3. Tissue concentrations of the wax are 0.34 mg/ml and 0.12 mg/g in the serum and liver respectively. 4. The presence of the wax esters in these two particular tissues suggests that the wax is synthesized in the liver, incorporated into lipoproteins, and functions as a lipid transport molecule.
