바위털갯지렁이, Marphysa Sanguinea 유생의 생존과 성장에 미치는 사육기질과 환수율의 영향

Abstract

Rockworm, Marphysa sanguinea is the most known polychaeta species with a high economic value. However, this species has a high mortality rate from the larval stage to the juvenile stage. The purpose of this study was to evaluate optimum rearing environments that affect survival and growth rates of rockworm larvae. Two different experiments were conducted to test the performance of substrate composition and water exchange rate for rockworm larvae culture. In the first experiment, substrates used for the experiment were decomposed granite soil (1~2 mm in diameter) 100%, sand (0.02~0.2 mm in diameter) 100%, oyster shell (5~10 mm in diameter) 100%, mixture of the sand and the oyster shell 50:50 ratio and mixed substrate(mixture of the gravel, the decomposed granite soil, the sand and the oyster shell 1:1:1:1 ratio). In the second experiment, larvae were maintained in five different water exchange rates no water exchange, one cycle/day, two cycles/day, three cycles/day and continuous exchange (one cycle means that whole water in a tank is replaced by new water one time a day). Each trial was conducted in triplicate for two months. Results showed that, appropriate substrates for rockworm larvae culture appears to be the sand/oyster shell mixed substrate (50:50 mixture) and the all substrate mixture. In addition, three cycles/day was economically the most efficient, although the continuous exchange showed the highest survival rate.