Controlled reproduction of an important indigenous fish species, Spinibarbus denticulatus (Oshima, 1926), in Southeast Asia.

摘要

Aquaculture of Spinibarbus denticulatus (Oshima, 1926), a fish species indigenous to North Vietnam and Eastern China, is constrained by lack of fingerlings for stocking ponds and cages. As these fish do not naturally breed in captivity, carp pituitary extract (CPE), luteinizing hormone-releasing hormone analogue (LHRHa) with domperidone (DOM) and human chorionic gonadotropin (HCG) were administered at various doses to induce ovulation. A first set of experiments evaluated the response to LHRHa (30, 40 and 50 micro g kg-1) with or without DOM (10 mg kg-1), CPE (20, 30 and 40 mg kg-1) and HCG (3000, 4000 and 5000 IU kg-1). A second set of experiments evaluated the dose response to LHRHa (30, 35, 40 and 50 micro g kg-1) primed with 6 mg kg-1 of CPE, and HCG (3000, 3500, 4000, 5000 IU kg-1) primed with 6 mg kg-1 of CPE. The treatment groups were compared with each other and the control (injected with 0.9% saline solution). Only 25% and 50% ovulation resulted when treated with LHRHa at 40 and 50 micro g kg-1, whereas 100% ovulation was achieved with an addition of DOM to LHRHa. Both 30 and 40 mg kg-1 CPE induced 100% ovulation. However, HCG (4000 and 5000 IU kg-1) induced ovulation in only 33% of females. When primed with CPE, the minimum dose of LHRHa required was 35 micro g kg-1 to achieve 70% ovulation. Priming HCG with CPE also resulted in 100% ovulation, and the minimum effective dose of HCG to induce ovulation was 3500 IU kg-1 with 60% ovulation. Fertilization and hatch rates observed in this study with different hormonal stimulation were high (80-93%). The results indicate that while the use of combined hormone strategy has no apparent advantage over a single hormone strategy, LHRHa+DOM (40 micro g kg-1+10.0 mg kg-1) and CPE (30 mg kg-1) are most effective in consistently inducing ovulation and thus can be used for commercial hatchery production of S. denticulatus larvae..