EGG COLLECTION FROM BROODSTOCKS OF YELLOW TAIL FED COMMERCIAL SOFT DRY PELLETS

Yellowtail Seriole quinqueradiata broodstocks, captured by set-net fis hery and reared on raw fish for one and a half years, were fed frozen raw fish (RF group), moist pellets (MP group), or soft dry pellets (SD P group) for 6 months before egg collection. The MP group received a 1 :1 diet mixture consisting of a formula feed prescribed by the Nationa l Research Institute of Aquaculture and raw fish, whereas the SDP grou p was fed a commercial soft dry pellet. After 6 months the fifth in ea ch net-cage were injected with hormone (HCG) to induce spawning, and e ggs were collected from each broodstock either after induced spawning or by strip spawning of adults followed by the dry method of inseminat ion. Parameters of the SDP group such as number of eggs per spawner, f ertilization rate, hatching rate, and survival rate of the larvae were compared with those of the RF and MP groups. The success of egg colle ction from the SDP group was as good as that from the MP group, and th ose from the SDP and MP groups were superior to that from the RF group . These results clearly indicated that both DP and MP were efficacious for broodstock management of yellowtail and their egg collection.