Temperature effect on the growth and gonad development of the Pacific Oyster Crassostrea gigas

Abstract

Growth and gonad development of the Pacific Oyster Crassostrea gigas was investigated in El Salvador and Korea. C. gigas was kept at three different water temperatures, 28 °C (normal temperature in tropical areas), 24 °C (optimal temperature for Crassostrea gigas) and 15 °C (normal temperature in winter in Korea). Oyster seeds and adults were set in three tanks at three different temperatures. Oysters were maintained during two months and checked fortnightly. A mixture of phytoplankton (Isochrysis galbana and Tetraselmis sp.) at the proportion of 50:50 was provided every day during the experiment. Growth of oyster increased at 15 °C while it decreased at 24 °C and 28°C. Growth rate was lowest at 28°C (ANOVA, p=0.002).. Experiment results were compared with data studied in El Salvador. For the oyster sampled randomly in El Salvador, the condition index trough the months sampled fluctuated from 7.4 % reported for the month of January 2013 being the lowest value, to the highest value reported with 18.1 % in November 2013. Condition index were significantly different by months ( p = 0.000).