Effects of adding sea mud into feed on water environmental factors and population density of Tisbe furcata under indoor breeding conditions

Tisbe furcata was cultured indoor in cement pools in seahorse teaching and researching base of Ludong University in Yantai city，Shandong province，China. By fed feed adding different amount of sea mud， the community densities of T. furcata were compared and the relationship between community density and water environmental factors，such as nitrite，nitrate，ammonia nitrogen and phosphate，were analyzed. The results showed that the community density of T. furcata fed by feed without adding sea mud was significantly higher（P<0.01）， which implied that high community density of copepods naturally growing in the sea cucumber breeding ponds could not directly use sea mud as their feed. Among nitrite，nitrate，ammonia nitrogen and phosphate，nitrite represented the most important one，because it was significantly correlated with copepods’ community density at the beginning. While when its concentration exceeded 0.4 mg/L，it would inhibit the growth of copepods. Therefore，nitrite should be monitored carefully during the aquaculture process. Phosphate was significantly correlated with copepods’ community density during its breeding.