Finfish Breeding and Hatchery Management

3.4.2. Dosage of ready-to-inject spawning agents

Unit 3 - Breeding of major carps

3.4.2. Dosage of ready-to-inject spawning agents (ovaprim, ovatide, WOVA-FH, etc.)

Females

• Catla : 0.4-0.5 ml/kg b.w.
• Silver carp : 0.4-0.7 ml/kg b.w.
• Rohu : 0.3-0.4 ml/kg b.w.
• Grass carp : 0.4-0.8 ml/kg b.w.
• Mrigal : 0.25-0.3 ml/kg b.w.
• Bighead carp : 0.4-0.5 ml/kg b.w.
• Fringe-lipped carp : 0.3-0.4 ml/kg b.w.
• Mahseers : 0.6-0.7 ml/kg b.w.
• Catfishes : 0.6-0.8 ml/kg b.w.

Males (all species of carps) : 0.1-0.3 ml/kg b.w.

Males (catfishes) : 0.15-0.4 ml/kg b.w.

Steroids

• An alternative approach is to use selected steroid hormones targeted at the oocytes. Most of the previous work on this subject is on induced ovulation in vitro.
• The effects of steroid hormones on ovulation are seen primarily as germinal vesicle breakdown (GVBD).
• GVBD is normally controlled by one or more steroids produced in the ovaries under gonadotropin stimulation, but the timing of ovulation related to that of GVBD varies.
• In vitro ovulation normally follows steroid induced GVBD in catfish (H. fossilis). The action of pituitary gonadotropins on final oocyte maturation is known to be medicated through steroid hormones.
• Deoxy corticosterone acetate (DOCA) and cortisone effectively stimulated in vitro ovulation in H. fossils.
• The available reports indicate that steroid hormones are quite potent in inducing spawning in cultivated fishes, but are yet to find commercial applications.
• The thyroid stimulating hormone is also reported to bring about ovulation in Indian catfish.
• Although there are no reports on the effects of pheromones on the reproduction of IMC, there are circumstantial evidences which suggest that pheromones secreted by IMC help in effecting spawning.
• Similarly, sympathetic spawning of carps in bundhs appears to be due to the release of pheromones.