A comparative field study of growth, survival and reproduction of Crassostrea gigas, C. angulata and their hybrids

Abstract

This paper reports a comparative study of two cupped oysters, Crassostrea gigas and C. angulata, and their hybrids reared in the Marennes-Oléron Sound (France) under usual farming conditions. The relative proficiency of these species was characterized in terms of growth, survival and reproduction, three major concerns for oyster farming. Four populations of each taxon were sampled (C. gigas: Japan and France; C. angulata: Taiwan and Spain) and used as progenitors to produce six different progenies under common hatchery and nursery conditions (transfer of 5 to 6 g of seed oysters at sea and rearing in bags for 2 years). Mortality profiles differed greatly among the progenies. The C. angulata progeny of Taiwanese origin gave the poorest results, with 100% mortality during the second year. For the entire rearing period, the highest yield (+22%) was obtained with the C. gigas progeny of French origin. The sexual maturation index, lipid cycles and dry weight loss after spawning showed that spawning of C. angulata was delayed by about two weeks compared to that of C. gigas. A clear maternal effect was observed for the growth and reproductive characteristics of the hybrids. On the whole, C. gigas of French origin gave the best aquacultural results. However, severe episodes of C. gigas mortality have been observed in France in recent years, indicating that this species might not be entirely suitable for sustained oyster farming in this country.

Spatio-temporal variations in biological performances and summer mortality of the Pacific oyster Crassostrea gigas in Normandy (France)

“…Such results corroborated the hypothesis of a negative impact of spawning on oyster survival, and suggest the spawning event to correspond to a critical period during which tissue restructuring and important metabolic changes occur. Nevertheless, in a study performed on C. gigas and C. virginica deployed in the Marennes-Ole´ron Basin, no positive correlation could be established between weight loss due to spawning and mortality; the only significant mortality peak for C. gigas occurred after spawning (Soletchnik et al 2002). According to Mori (1979), over-maturation, ''a pathological phenomenon caused by a long residence of ripe oocytes or sperms in the gonad'', seemed even to accelerate oyster mass mortality.…”

Benthic macrofauna and sediment reworking quantification in contrasted environments in the Thau Lagoon

“…1). The Thau Lagoon is the largest shellfish breeding area in Europe (Soletchnik et al, 2002) and yearly produces about 35 000 tons of shellfish (Hamon and Tournier, 1981;Gangnery et al, 2003). This lagoon is connected to the sea through the narrow channels of Sète and receives freshwater mostly from the north shore.…”

Growth and economic performance of diploid and triploid Pacific oysters Crassostrea gigas cultivated in three lagoons of the Gulf of California

“…Due to its fast growth (Taris et al, 2007), resistance to variations of temperature and salinity (Flores-Vergara et al, 2004), meat quality (Langdon et al, 2003), shell shape (Ward et al, 2000), and disease resistance (Villanueva-Fonseca & EscobedoBonilla, 2013), this species has been introduced in many countries of the world (Soletchnik et al, 2002), including Mexico. Despite of the growing interest for its cultivation, there are still some factors that need to be studied to support the economy of this industry, such as genetics and specific strains adapted to local conditions of new cultivation sites.…”