Received: 23-10-2023 / Accepted: 07-03-2024
This study aimed to determine the optimal fertilization method in the process of artificial reproduction of Spotted scat. A total of 18 pairs of parent fish were selected to participate in spawning trails based on the levels of gonad maturation. Females were injected twice at 24h interval by the hormone LHRH-a (20 and 50 µg/kg), while male fish were induced once by the hormone HCG (200 IU/kg) at the same time as the second injection of the female. After hormone injection, fish were randomly selected and assigned into 3 groups including Group 1: 6 pairs used to investigate natural fertilization in composite tanks; Group 2: 6 pairs used to investigate natural fertilization in a 6m3fabric cage located at the broodstock breeding area and group 3: 6 pairs fertilized by stripping method. The results showed that the natural spawning rates of groups 1 and group 2 were 66.7% and 83.3%, respectively. However, the rate of fertilized eggs in these groups was 0%. For fish in group 3, the spawning rate of fish was 83.3%, and the rate of fertilized eggs was quite high as 86.2%. This indicates that the “dry method” by stripping eggs and sperms from brooders is the optimal method for the artificial reproduction of Spotted scat up to the present time.