title: Management of Sexual Maturation and Natural Spawning of Captive- Reared Yellowtail Kingfish, Seriola lalandi, in an Indoor Rearing Tank.
abstract: This study describes results on sexual maturation and characteristics of natural spawned eggs to develop a method for the production of stable, healthy fertilized eggs from captive-reared yellowtail kingfish, Seriola lalandi. A total of 59 yellowtail kingfish were captured off the coast of Jeju Island, after which the broodstock was cultured in indoor culture tank (100 m(3)) until they were 6.1-14.9 kg in body weight. As part of the rearing management for induced sex maturation, the intensity of illumination was maintained at 130 lux. The photoperiod (light/dark; L/D) was set to a 12 L/12 D from October 2013 to January 2014, and 15 L/9 D from February 2014 to June 2014. Feeds comprised mainly EP (Extruded Pellets), with squid cuttlefish added for improvement of egg quality, and was given from April to June 2014. The first spawning of yellowtail kingfish occurred in May 3, 2014, at a water temperature of 17.0°C. Spawning continued until June 12, 2014, with the water temperature set at 20.5°C. Time of spawning was 26 times at this period. The total number of eggs that spawned during the spawning period was 4,449×10(3). The buoyant rate of spawning eggs and fertilization rate of buoyant eggs during the spawned period were 76.1% and 100%, respectively. The diameters of the egg and oil globule were 1.388 ± 0.041 mm and 0.378 ± 0.029 mm, respectively, which was higher in early eggs than in those from late during the spawned period.
authors.affiliation: Jeju Fisheries Research Institute, National Institute of Fisheries Science, Jeju 63610, Korea.
authors.forename: Sang Geun
authors.initials: SG
authors.lastname: Yang
authors.affiliation: Jeju Fisheries Research Institute, National Institute of Fisheries Science, Jeju 63610, Korea.
authors.forename: Seung Cheol
authors.initials: SC
authors.lastname: Ji
authors.affiliation: Jeju Fisheries Research Institute, National Institute of Fisheries Science, Jeju 63610, Korea.
authors.forename: Sang Gu
authors.initials: SG
authors.lastname: Lim
authors.affiliation: Marine Science Institute, Jeju National University, Jeju 63333, Korea.
authors.forename: Sang Woo
authors.initials: SW
authors.lastname: Hur
authors.affiliation: Jeju Fisheries Research Institute, National Institute of Fisheries Science, Jeju 63610, Korea.
authors.forename: Minhwan
authors.initials: M
authors.lastname: Jeong
authors.affiliation: Marine Science Institute, Jeju National University, Jeju 63333, Korea.
authors.forename: Chi Hoon
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Jeju Fisheries Research Institute, National Institute of Fisheries Science, Jeju 63610, Korea.
authors.forename: Bong Seok
authors.initials: BS
authors.lastname: Kim
authors.affiliation: Marine Science Institute, Jeju National University, Jeju 63333, Korea.
authors.forename: Young-Don
authors.initials: YD
authors.lastname: Lee
keywords: Fertilization rate of buoyant eggs; Induction sexual maturation; Natural spawning; Seriola lalandi; Yellowtail kingfish