Biochemical and energy changes during embryogenesis in the rock scallopCrassadoma gigantea

Abstract

Abstract. The biochemical composition of eggs spawned from rock scallops Crassadoma gigantea (Gray) collected from Clayoquot Sound, Vancouver Island (British Columbia, Canada) in the winter of 1987 and the summer of 1988, differed significantly only in lipid and soluble-ash contents. Major macronutrients were catabolized simultaneously and linearly with time of embryogenesis. Total egg energy expended during development was 11.8 kJ g-1 derived 46.7, 9.8 and 43.5%, from lipid, carbohydrate, and protein, respectively. Glucose in the egg was the dominant source of carbohydrate energy. Deposition of shell was linear with time of embryogenesis and the formation of 44.8% dry wt of shell in the early larval stage, referred to as the D-larva, consumed 64.4% of the total energy expended. Energy required for shell formation was 17.55 kJ g-1. The RNA:DNA ratio declined exponentially from 18.6 in the egg to 2.21 in the D-larva, which was consistent with that of adult bivalves. Many changes in fatty acid composition were linear with time of embryogenesis, and the percentage of n3-and n6-higher unsaturated fatty acids to total polyethylenic acids exhibited significant declining and increasing trends, respectively. The linear rate of catabolism of eicosapentaenoic acid, 20:5n3, and the constant level of docosahexaenoic acid, 22:6n3, illustrated an energy and a structural role, respectively, for these dominant acids in the embryonic development of the rock scallop.

Variation in Lipid, Protein, and Carbohydrate Content During the Embryonic Development of the Crayfish Cherax Quadricarinatus (Decapoda: Parastacidae)

“…This increase in the use corresponds to hatching and could be explained by a higher energy demand for the differentiation and growth processes occurring in postembryo stages. Similar phenomena for protein depletion have been established for various crustacean species (Holland, 1978;Murugadass and Pandian, 1991;Clarke, 1992;Chu and Ovsianico, 1994;Biesiot and Perry, 1995;Roustaian and Kamarudin, 2001), for mollusks (Fraser, 1989;Whyte et al, 1990;Videla et al, 1998), and for fish (Rønnestad et al, 1998;Sargent et al, 1999). However, the strategies for energy use are varied.…”

“…This proportion is very common among eggs of aquatic invertebrates, especially crustaceans (Holland, 1978;Whyte et al, 1990;Clarke, 1992). It is generally accepted that protein is the major component Sandeman and Sandeman (1991).…”

“…Many authors have analyzed the biochemical changes in different organisms, such as fish (Watanabe et al, 1984;Petersen and Anger, 1997;De Silva et al, 1998;Rønnestad et al, 1998;Mookerji and Ramakrisha, 1999); crustaceans (Pandian, 1970;Clarke et al, 1990;Chu and Ovsianico, 1994;Lovrich and Ouellet, 1994;Rodríguez et al, 1994;Biesiot and Perry, 1995;Mourente et al, 1995;Petersen and Anger, 1997;Palacios et al, 1998;Lemos and Rodríguez, 1997;Cavalli et al, 2000;Roustaian and Kamarudin, 2001); and mollusks (Fraser, 1989;Whyte et al, 1990;Heras et al, 1998;Laing and Earl, 1998). From these studies, it is generally accepted that lipids, particularly tryglycerides, are the main energy supplier during embryonic development.…”

Utilization of lipids during early development of the sea urchin Evechinus chloroticus

“…The greatest reliance on stored energy reserves is in Stages 1 and 3. The energy for Stage 1 is provided to the embryo by the adult during vitellogenesis (Bayne et al 1975, Bayne 1976a, Whyte et al 1990, and for Stage 3 by feeding during the planktonic phase (Bayne 1972, 1976a, Whyte et al 1989, 1990.…”

Differences in Egg Quality and Larval Development among Four Populations of Sea Squirt Halocynthia roretzi Adults

“…4.5 0.0%, 4.6 0.1%, 4.4 0.0%, 3.6 0.0% , . (Watanabe et al, 1984;Fraser et al, 1987;Tomas et al, 2005), (Whyte, 1987;Whyte et al, 1990;His and Maurer, 1988) (Holland and Spencer, 1973;Waldock and Nascimento, 1979) (Ringo et al, 1987;Sargent et al, 1989).…”