Morphological Development of Eggs, Larvae and Juveniles of the Sterlet Sturgeon, Acipenser ruthenus (Pisces: Acipenseridae)

스텔렛 철갑상어 (Acipenser ruthenus)의 난 발생과 자치어 형태발달

To develop cultivation technique for Acipenser ruthenus and secure basic taxonomic materials, this study examined egg development and larva morphological development. This study used a couple of male and female broodstork matured in a PVC circle water tank (Ø 5 m) with the water temperature of $16.0{\pm}1.0^{\circ}C$ in June 2005. They were oval opaque and sinking cohesive eggs and the sizes of them were between $3.83{\sim}3.85(3.84{\pm}0.01)mm$ (n=10). As for the egg development, the dry process was adopted with artificial insemination in this study, and an hour after the insemination, the embryo disks were developed, 31 hours after the insemination, they reached the end of gastrula stage, and 82 hours (50%) after the insemination, they were hatched. Right after the hatch, the total lengths of larvae were $10.1{\sim}10.3(10.2{\pm}0.11)mm$ (n=10) with big yolks in the venter. 17 days after the hatch, the total lengths of them were $26.2{\sim}32.4(29.3{\pm}4.39)mm$ (n=10) and in the front of a dorsal fin there were 11 scute scales that started to make tracing development. As 50 days after the hatch, the total lengths were $86.4{\sim}93.1(89.8{\pm}4.71)mm$ (n=10), and fin rays all reached integer, they were moved to the larva apparatus.

스텔렛 철갑상어 Acipenser ruthenus의 양식기술 개발 및 분류학적 기초자료를 확보하기 위하여 난 발생 및 자치어 형태 발달을 조사하였다. 친어는 2005년 6월에 PVC 원형수조 (Ø 5 m) 수온 $16.0{\pm}1.0^{\circ}C$에서 성숙시킨 암수 1쌍을 사용하였다. 난은 타원형의 불투명한 침성 점착란으로 크기는 $3.83{\sim}3.85(3.84{\pm}0.01)mm$ (n=10)였다. 난 발생은 건식법으로 인공수정 시켰고, 수정 1시간 후에 배반이 형성, 수정 31시간 후에 낭배말기에 도달하였으며, 수정 82시간 (50%) 후에 부화하였다. 부화 직후 자어는 전장 $10.1{\sim}10.3(10.2{\pm}0.11)mm$ (n=10)로 복부에 큰 난황을 달고 있었다. 부화 17일 후에는 전장 $26.2{\sim}32.4(29.3{\pm}4.39)mm$ (n=10)로 등지느러미 앞쪽이 11개의 굳비늘이 흔적 적으로 발달하기 시작하였다. 부화 50일 후에는 전장 $86.4{\sim}93.1(89.8{\pm}4.71)mm$ (n=10)로 지느러미 기조가 모두 정수에 도달하여 치어기로 이행하였다.