博士 / 國立臺灣海洋大學 / 海洋生物研究所 / 104 / First feeding of marine fish larvae is a critical step in the establishment of a successful aquaculture production, and it is currently relied on the productions of live preys. Recently, copepods have been paid great attention as supplementary diets for larviculture due to their higher nutritional value and palatability compared to the conventional live preys (e.g. Artemia and rotifers). This thesis aims to investigate: (1) the optimal culture conditions of two copepod species Acartia bilobata and Apocyclops royi, (2) viabilities of cold-stored eggs of two strains of A. bilobata, (3) effects of thermal selective breeding on A. royi, (4) feeding suitability of copepod-based diets on larval fish.
Chapter two shows the effects of algal diets and salinities on the production of cyclopoid copepod A. royi. The two-species diet consisted of Isochrysis galbana and Nannochloropsis oculata was the most supportive diet for the female fecundity, population growth and fatty acid profile of A. royi. In addition, based on the comparisons of fatty acid compositions between copepods and microalgal diets, we suggest that A. royi have the ability to synthesize long chain polyunsaturated fatty acids (PUFA) (e.g. eicosapentaeonic acid, EPA and docosahexaneoix acid, DHA) from shorter chain fatty acids. On the other hand, 20 is the optimal salinity for attaining their highest productivity, and salinity had varying influences on A. royi across different developmental stages.
Two objectives were placed in chapter three including the investigation of photoperiodic effects on egg production and hatching rate, and the viability of cold-stored eggs of tropical calanoid copepod Acartia bilobata. Medium photoperiods (16L: 8D, 12L: 12D and 8L: 16D) are suitable for attaining the high egg production, whereas the reduced diapause production occurred in the full-dark treatment. In the experiments of egg cold storage, we found that the long-term acclimated culture strain produced less proportion of diapausing egg, and the quiescent eggs had higher cold storage capacities.
In chapter four, the novel approach of selective breeding based on temperature control (28°C→18°C→28°C) was performed to enhance the aquaculture potential of the cyclopoid copepod A. royi. The constant larger female size and higher nauplii production were obtained in the selective strain. The compensative enhance of fatty acid content showed in the first generation when the selective strain was transferred back at given temperature (28°C), but it was not sustainable in the later generations.
Chapter five addresses the effects of different copepod-based diets on the first feeding of three marine fish species. The results indicated that although A. royi provides fair fatty acid profile, it is likely to be the sub optimal prey for larval batfish Platax orbicularis and longsnout seahorse Hippocampus reidi due to their swimming velocity and pattern. The naupliar Acartia tonsa derived from the cold-stored eggs offer the high proportion of DHA, EPA and total PUFA, and it can be a supportive diet for enhancing the survival and growth of gilt-head sea bream (Sparus aurata) larvae.
| Identifer | oai:union.ndltd.org:TW/104NTOU5270011 |
| Date | January 2016 |
| Creators | Pan, Yen-Ju, 潘彥儒˙ |
| Contributors | Hwang, Jiang-Shiou, 黃將修 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | en_US |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 176 |
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