Korean bullhead (Pseudobagrus fulvidraco) was collected from the Kum River areas of Kangkyung-eup, Nonsan city, Chungcheongnam-do, Korea, from April to June, 2012 and was fertilized in order to observe egg development and temperature-related cleavage rates and mitotic intervals (). The fertilized eggs were separative, demersal and light yellowish with in diameter, and did not contain oil globules. The first cleavage stages were 90 min, 80 min, 60 min and 50 min at , , and , respectively. At higher temperatures, eggs developed faster and underwent further identical development. For Korean bullhead, were min at , min at , min at and min at . There were strong negative correlations between the and water temperatures at all points studied (Y=-1.13X+58.15, =0.98, n=30, where Y is and X is temperature). The results obtained in this work will be helpful for chromosome manipulation by use of cleavage frequency data and data in Korean bullhead.

The effects of ovulation induction in ussurian bullhead, Leiocassis ussuriensis, were investigated by treating ussurian bullhead with hCG, LHRHa, GnRHa, ovaprim, and pimozide. hCG was injected to ussurian bullhead at 0.75% NaCl, 5,000, 10,000, 20,000, and 30,000 IU, respectively. The ovulation inducement rates were 100% in 20,000 and 30,000 IU. Fertilization rates were 82.7% and 79.8%. Hatching rates were 59.4% and 57.2%. Ovulation time was between 16-19 hr The concentrations of LHRHa injected were 0.75 NaCl, 50, 100, 200, 300, and . The ovulation inducement rates were 100% in 300 and . Fertilization and hatching rates were 84.9% and 68.4% at . The times to ovulation were between 23 hr and 34 hr. Ovaprim of 0.75% NaCl, 1.0, 1.5, 2.0, 2.5 and 3.0 ml/kg were injected to the abdominal cavity. The ovulation inducement rate was highest at 2.0 and 3.0 ml/kg to 92% and ovulation time was between 27-38 hr. LHRHa concentrations of 0.75% NaCl, 50, 100, 200, 300 and were injected with pimozide (). Ovulation inducement rate was 100% from 200 to 400 IU with pimozide. Ovulation time was 22-36 h. Fertilization and hatching rates were 88.9% and 70.4% in with pimozide.

This japonica cultivar was developed from a cross between two F₁ hybrids of YR13168 (Milyang 95/Iri390) and YR13198 (Milyang101/Iri390) using anther culture. It has about 104 days of growing duration from seeding to heading and relatively short