Blood Chemistry, Biochemical Composition, and the Annual Reproductive Cycle in the Giant Scallop, Placopecten magellanicus , from Southeast Newfoundland

Gametogenesis in the giant scallop, Placopecten magellanicus (Gmelin), occurs in early summer and spawning takes place during August and September. The gonad differentiates between March and May, when the water temperature is low (0 to −1 °C) and food supply high. Gonad growth also begins at this ti...

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Bibliographic Details
Published in:Journal of the Fisheries Research Board of Canada
Main Author: Thompson, R. J.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1977
Subjects:
Online Access:http://dx.doi.org/10.1139/f77-277
http://www.nrcresearchpress.com/doi/pdf/10.1139/f77-277
Description
Summary:Gametogenesis in the giant scallop, Placopecten magellanicus (Gmelin), occurs in early summer and spawning takes place during August and September. The gonad differentiates between March and May, when the water temperature is low (0 to −1 °C) and food supply high. Gonad growth also begins at this time. Energy reserves from the previous year do not seem to play a significant part in subsequent growth and maturation of the gonad. There is no accumulation of metabolic reserves in the scallop gonad after spawning; in winter, the gonad is very small and inactive. Levels of lipid (mostly phospholipids and free sterols), protein, low molecular weight carbohydrate, and glycogen increase in the plasma during the period of gonad growth and maturation. The amount of glycogen in the circulating hemocytes is greater in summer than in winter. Key words: Placopecten magellanicus, bivalve, scallop, reproductive cycle, blood, hemolymph, hemocyte, blood chemistry, glycogen, phospholipid, sterol