Biochemical Changes Associated with Embryonic and Larval Development in the American Lobster 'Homarus americanus' Milne Edwards

摘要

Proximate analysis was carried out on developing Homarus americanus Milne Edwards larvae and eggs. Lipids were further analyzed for class and fatty acid composition. During embryogenesis, triacylglycerol supplied most of the energy and the fatty acid 20:5 was selectively utilized. Absence of prolonged cold incubation temperatures resulted in increased yolk reserves in newly hatched larvae. Weight, ash, protein, carbohydrateemetamorphic larvae while large triacylglycerol reserves were stored in postmetamorphic (fourth stage) animals. Absolute levels of metabolic reserves limited the extent of their utilization. Triacylglycerol was the preferred (first used) energy substrate but was usually limited in amount; hence protein was the major source of metabolic energy during starvation in premetamorphic larvae. Dietary intake of carbohydrate and possible protein based gluconeogenesis were responsible for most chitin synthesis as established carbohydrate reserves were not sufficient.