본 연구의 목적은 능성어와 자바리의 정자동결을 위한 간편한 실험법개발이다. 희석제와 동해 방지제가 정자동결에 미치는 효과를 파악하고자 운동성성과 생존율을 조사하였다. 동결실험에 서 300 mM glucose와 15% dimethylsulfoxide (DMSO)를 희석제와 동해방지제로 각각 사용하였 다. 동결실험결과, 능성어 정자는 동결 5개월 후 60% 이상의 운동성을 보였고, 자바리 정자는 동결 5개월후 90% 이상의 운동성을 보였다.
This study is conducted to monitor the morphological developmental features of the egg development, larvae and juvenile of Epinephelus septemfasciatus, the fertilized eggs were gotton using artificial insemination. Matured parents are collected from marine caged fish farms in Geomun-ri, Samsan-myeon, Yeosu-si, Jeollanamdo Korea in June 2012. The fertilized eggs were pelagic eggs containing one oil globule, and measured 0.81~0.89 mm (0.85±0.04 mm, n=50) in diameter. In regard to rearing environment, the water temperature is 21.0~23.0℃ and the salinity is 32.0~33.2‰. Hatching was observed from 48 hours after fertilization, the mouth and anus of prelarvae was not opened but had egg yolk at newly hatched. 4 days after hatching, the mouth and anus of postlarvae was opened and began to eat Rotifer and was measured 2.40~2.49 mm (2.45±0.03 mm n=10) in total length. 12 days after hatching, postlarvae was measured 3.77~4.67 mm (4.27±0.33 mm) in total length, its the second pole tide of dorsal fin and the first pole tide of pelvic fin was extended longitudinally. 71 days after hatching, juvenile was measured 40.5~45.4 mm (42.6±2.04 mm) in total length. Seven bands were observed in body, and pole tides of dorsal and pelvic fins were shortened.
The fertilized eggs of E. septemfasciatus are spherical and transparent with buoyancy at 790 to 890 μm (average 821.8±2.0 μm) in diameter with 170 to 230 μm oil globules (average 192.9±0.93 μm). Hatching began approximately 46 and 35 hours after fertilization at 22.0℃ and 25.0℃ water temperature, respectively. The average total length of newly hatched larvae was 1.75±0.03 mm. Most of the yolk and oil globules were absorbed within 3 to 4 days after hatching. The larvae reached 2.48 to 2.72 mm in total length, and their mouths and anuses opened at 3 to 4 days after hatching. In this time, the mouth diameters of the larvae were 0.209 to 0.238 mm. The larvae reached 3.24 to 4.15 mm in total length at 11 to 17 days after hatching, and began to metamorphose at the time the second dorsal and pelvic spines appeared and elongated. The abdominal cavity was densely lined with melanophores. The larvae reached 5.12 mm in total length at 24 days after hatching.