Induced spawning of native threatened spotted snakehead fish Channa punctatus with Ovaprim.

摘要

The spotted snakehead, Channa punctatus, is one of the native threatened fish species in India. In the present study the efficacy of Ovaprim in stimulating ovulation and spawning performance of this candidate fish was examined under captive condition. A total of 9 matured female and 18 male fishes with weights ranging from 63 to 80 g, were randomly selected for three hormone dosages. Both male and female fishes in each hormone dosage were administered a dose of 0.2, 0.4, and 0.6 mL of Ovaprim/kg body weight (BW) respectively. Each breeding set consisted of two males and one female. The hormone-administered fishes were then placed into the concrete cement tanks for spawning. The breeding performance was assessed based on the number of eggs spawned, spawning response, percentage fertilization and percentage hatching. Partial spawning was observed with a dose of 0.2 ml Ovaprim/kg BW, while complete spawning was noticed in the medium dose (0.4 ml of Ovaprim/kg BW) and higher dose (0.6 ml of Ovaprim/kg BW) administered fishes. The highest number of eggs spawned (p<0.05) was recorded when the females were injected with 0.4 ml of Ovaprim/kg body weight than those injected with other doses. The latency period and number of spawned eggs ranged from 24-31 hrs and 2,164-6,538 respectively. The highest fertilization (97.6%) and hatching rates (96.3%) were also observed at the medium dose (P<0.05). With regard to hatching rates, no significant difference was noticed between the medium and low doses of Ovaprim administered groups. From the present study, it is evidenced that the synthetic gonadotropin-releasing hormone with a dopamine antagonist at a dose of 0.4 ml/kg BW could be used as an appropriate spawning agent for successful breeding and seed production of C. punctatus under captive conditions.