Abstract
The cyprinid loach, Misgurnus mizolepis $G\ddot{u}nther$, a freshwater teleost, is a member of the family Cobitidae and is known to distribute in Korea and China. This fish is considered to be an excellent food fish in Korea. This report is a description of the gross morphology of the embryos and larvae up to the development of juvenile period of life. The eggs were obtained by injecting gonadotropin and fertilized by wet method in the laboratory on July 10 in 1986. The inseminated eggs were rinsed with tap water and incubated at $25^{\circ}C$. Live, freshly laid eggs were separative, demersal, adhesive, light yellow and average 1.1mm in diameter. The hatching took place in about yellow and average 1.1mm in diameter. The hatching took place in about 24 hours after fertilization. The newly hatched larvae were average 2.7 mm in total length possessing yolk sac and 35-36 myotomes. Ten hours after hatching, the prelarvae attained 3.5 mm in total length. The first heart pulse and melanophores at the side of the body were observed at this stage. Yolk sac was completely reserved at four days after hatching. The larvae that was cultured 24 days after hatching, 15.4-16.4 mm in total length, entered the juvenile period of life. All the un rays were already peresent; D. III 6, A. III, 5, P.10, V. 4-5, C.14.
실내사육중이던 미꾸라지 친어에 생식선자극 호르몬을 복강주사하여 20시간 후인 1986년 7월 10일에 얻은 난을 인공수정시켜 난발생과정과 부화자어의 성장에 따른 형태변화에 대해 관찰한 결과를 요약하면 다음과 같다. 성숙란은 난경이 $1.04\~1.18mm$(평균 1.12mm, n=25)로 난막은 아주 얇으며, 담황색을 띤 분리침성 점착난이다. 사육수온 $25^{\circ}C$에서 수정후 약 24시간만에 첫 부화가 일어났다. 부화직후의 자어는 전장이 $2.60\~2.80mm$ 두부는 난황 앞쪽 아래에 위치하며, 근절수는 $35\~36$개 이다. 부화후 4일째의 자어는 금장이 $5.10\~5.40mm$로 난황이 완전히 흡수되고 소화관이 발달한다. 부화후 16일째의 자어는 전장이 $9.4\~10.1mm$로 각 지느러미의 기조가 분화하며, 몸전체에 걸쳐 흑색소포가 골고루 분포한다. 부화후 24일째의 자어는 전장이 $15.40\~16.40mm$로 각 기조가 정수에 달하여 치어기에 이른다.