Induction of Ovulation by Hormone Treatment in Ussurian Bullhead Leiocassis ussuriensis

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 300 g/kg. The ovulation inducement rates were 100% in 300 and 400 µg/kg. Fertilization and hatching rates were 84.9% and 68.4% at 200 µg/kg. 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 400 µg were injected with pimozide (1,000 µg). 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 200 µg/kg with pimozide.