Captive Breeding, Rearing, and Effects of Different Diets on Reproduction of Longsnout Seahorse, Hippocampus reidi

• Main Authors: Wu, Guan-Ru, 吳冠儒
• Other Authors: Nan, Fan-Hua
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/xkx6zb

碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 106 === There are two main projects in this study. First, Neocaridina denticulate and Litopenaeus vannamei were employed as preys of Hippocampus reidi to explore the impact of vitamin E on the breeding of H. reidi. In the meanwhile, the optimum concentration of vitamin E for enriching preys was testified. Second, we explored the ideal sex ratio combination of H. reidi for a successful mating and recorded the mating behaviors. By combining the optimum results from both projects, we then launched a trial of commercial breeding and recorded all details as well as observations (including hatching, rearing, a serial of forage organisms and juvenile development) throughout this trial. Experiment I: four diets, including N. denticulate (Nd, Control), N. denticulate enriched with 0.5 % vitamin E (eNd), L. vannamei (Lv), L. vannamei enriched with 0.5 % vitamin E (eLv) were employed in a 12-week-long feeding experiment. The results showed that eLv group had the highest reproductive frequency (6.00 ± 1.41 times) and the lowest reproductive cycle (8.08 ± 0.95 days), suggesting that eLv is the best nourishment among four diets in promoting H. reidi reproduction. Experiment II: H. reidi were fed with L. vannamei enriched with three different concentrations of vitamin E (0.5 %, 1.0 %, 2.0 %, respectively) for 12 weeks. The results showed that the group having 0.5 % vitamin E-enriched L. vannamei had the highest reproductive frequency (5.50 ± 0.71 times). There were no significant differences in the reproductive cycle and the average number of larvae production found among different diets (p > 0.05). Experiment III: three different sex ratio combinations were tested for a 12-week-long mating experiment. They were: 1 female: 1male (1F:1M), 1 female: 2 males (1F: 2M), and 2 females: 1male (2F: 1M). All three groups were fed 0.5 % vitamin E-enriched L. vannamei, the best nourishment found in the experiment II. Results showed that the reproductive frequency in 1F:1M group (5.00 ± 0.00 times) was significantly higher than those in other groups (p < 0.05); there was no significant difference (p > 0.05) of the reproductive cycle as well as the average number of larvae production among three groups. Additionally, it was observed that female seahorse in the group 2F: 1M failed to put eggs into brood pouch, leading to an unsuccessfully mating. Experiment IV: according to the finest results gathered from above experiments, a trial of commercial breeding was launched in a 300-day duration that broodstock of H. reidi were fed with 0.5 % vitamin E-enriched L. vannamei and they were paired in a sex ratio combination 1F:1M. All information related to this trial was recorded. An average survival rate of 39 ± 14 % was obtained in this trial.