Egg Development and Juvenile Growth of the Pacific Cod Gadus macrocephalus (Korean East Sea Population)

摘要

Egg development and juvenile growth of the Pacific cod Gadus macrocephalus (Korean East Sea Population) were studied to increase fry production using mass cultivation. The eggs were rectangular and adhesive sinking type. The egg size and fertilizationrate were. 1.01-1.09 mm and 72.4%, respectively. The cumulative times for egg hatching at 3, 6, 9, and 12deg C were 600, 360, 240, and 192 hrs, respectively. The hatching rates at 3, 6, 9, and 12deg C were 60.2, 68.9, 62.5, and 40.6%, respectively. After 11, 45, and 90 days, the larvae grew to a total length of 5.46-5.99, 9.42-10.06, and 23.0-32.0 mm, respectively. At 100 days from hatching, they grew to an average of 30mm with a 7.1% survival rate. By 312 days, juveniles with a total length of 3.6 cmgrew to a total length of 14.7-20.1 cm and a body weight of 38.4-73.9 g. The specific growth rates of total length and body weight of the juveniles were 0.50% and 1.12%, respectively.