Effectiveness of carp pituitary extract and luteinizing hormone releasing hormone analogue administration (by either injection or cholesterol pellet implantation) on spawning performance in female sturgeon, Huso huso

The effectiveness of common carp pituitary extract (CPE), luteinizing hormone releasing hormone analogue (LHRH-A2) injections and LHRH-A2 implants for spawning induction in female sturgeon, Huso huso was examined. In the first trial, fish were injected with 7% physiological saline (control), 50 mg kg−1 CPE or LHRH-A2 at 3.5, 7, 8 or 10 μg kg−1. In the second trial, fish were treated with LHRH-A2 cholesterol pellet implants containing 0, 3.5, 7, 8 and 10 μg kg−1 LHRH-A2. Ovulated eggs were removed using a minimally invasive surgical technique and were artificially fertilized. Injection of CPE and LHRH-A2 at doses of 3.5, 7, 8 and 10 μg kg−1 resulted in the number of ovulated fish more than LHRH-A2 implants (similar doses) or controls, although there was no significant difference at doses of 8 and 10 μg kg−1 (P ≥ 0.05). The latency period of fish receiving CPE and LHRH-A2 injections was approximately 20 h, which was significantly lower than in fish receiving LHRH-A2 implants (P ≤ 0.05). Furthermore, there were no significant differences in rates of fertilization or hatching among the progeny produced in any of the treatment groups (P ≥ 0.05). In conclusion, the data from this study could be useful for artificial propagation of not-fully-matured females of H. huso at sturgeon hatcheries.

Huso huso, CPE, LHRH-A2, injection, implant, reproduction