Browsing by Author "Rodriguez Jr., Jesus C."
Amino and fatty acid profiles of wild-sourced grouper (Epinephelus coioides) broodstock and larvae VR Alava, FMP Priolo, JD Toledo, JC Rodriguez Jr., GF Quinitio, AC Sa-an, MR de la Peña & RD Caturao - In MA Rimmer, S McBride & KC Williams (Eds.), Advances in grouper aquaculture, 2004 - Australian Centre for International Agricultural Research
Series: ACIAR Monograph 110This study was undertaken to provide information on the levels of amino acids in the muscle, liver and gonad of wild-sourced broodstock and larvae, as well as in neurula eggs and day 35 larvae from a hatchery. The fatty acid composition of grouper broodstock tissues was also determined. Samples were analysed for crude protein, amino acids, total lipids and fatty acid contents. Muscle contained higher levels of crude protein and amino acids than the ovary and liver. At the early maturing stage, the grouper ovarian protein was 73.3% and lipid was 19.3%, indicating the high dietary requirements of these nutrients for ovarian development. The crude protein and amino acid contents in wild-sourced larvae were higher than that in eggs and larvae from the hatchery.
Book chapterVR Alava, FMP Priolo, JD Toledo, JC Rodriguez Jr., GF Quinitio, AC Sa-an, MR de la Peña & RD Caturao - In MA Rimmer, S McBride & KC Williams (Eds.), Advances in grouper aquaculture, 2004 - Australian Centre for International Agricultural Research
Series: ACIAR Monograph 110The main objectives of this project were to study the lipid chain transfer from the egg stage through hatching and the patterns of lipid conservation or loss during starvation and feeding of larvae in order to elucidate the lipid metabolism of grouper (Phase 1); to determine the fatty acid composition of highly unsaturated fatty acid (HUFA) boosters and enriched live food organisms to enable the possibility of choosing food organisms that provide various dietary levels and ratios of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (ARA, Phase 2); and to determine the effect of Brachionus and Artemia, containing different levels and ratios of DHA:EPA:ARA, on the growth and survival of grouper larvae (Phase 3). Total lipids (TL) of samples were extracted and separated into neutral (NL) and polar lipids (PL). The samples collected in Phase 1 were floating neurula eggs, newly hatched (NHL) and unfed 4-day larvae; larvae fed with live food organisms for 25 and 35 days or starved for 3 days; and wild-sourced larvae starved for a week. In Phase 2, the samples collected were phytoplanktons, Brachionus cultured in phytoplankton for 4 days, Diaphanosoma celebensis and Pseudodiaptomus annandalei. In phase 3, larvae were fed Brachionus until day 14 and at day 25 with Artemia. E. coioides eggs contained high DHA, EPA and ARA, demonstrating their importance in larval development. Larvae primarily spent NL as energy, whereas PL was generally conserved. Wild grouper larvae had higher levels of PL than NL, whereas hatchery-sourced eggs and larvae contained higher levels of NL than PL. Based on the lipid content of wild larvae, high phospholipid diets were essential for larvae survival and normal development. A variety of products were effective in enriching the HUFA content (particularly ratios of DHA, EPA and ARA) of live food organisms. HUFA-enriched live food organisms enhanced the growth, survival and pigmentation in grouper larvae.
Book chapterJD Toledo, D Chavez & JC Rodriguez Jr. - In MA Rimmer, S McBride & KC Williams (Eds.), Advances in grouper aquaculture, 2004 - Australian Centre for International Agricultural Research
Series: ACIAR Monograph 110This study was conducted to improve the hatchery survival of Epinephelus coioides by verifying and incorporating laboratory-scale experimental results to a hatchery-scale operation. Nine units of 200 m2 ponds were used to verify mass culture techniques for zooplankton. Three fertilization schemes were tested with 3 replicate ponds per fertilization treatment. To test copepod production in tanks, adults and copepodids were transferred into 6 production tanks at a density of 60 individuals/litre. Zooplankton in 3 of the tanks were fed daily with Nannochloropsis sp., Tetraselmis sp. and Chaetoceros sp., whereas zooplankton in the remaining 3 tanks were fed daily with half the amount of the mixture of algae and bread yeast. Larval rearing runs were performed from 2000-2002 to verify earlier experimental results. To propagate copepod nauplii in larval tanks, Acartia were inoculated in 4 larval rearing tanks, 2-3 days before stocking of grouper eggs or newly hatched larvae. Brachionus were added daily from day 2 to 18 at increasing densities. Artemia nauplii and metanauplii were fed to satiation from day 15 until metamorphosis. Pond-grown zooplankton was added in separate tanks from day 15 onwards as a supplement to Artemia. The population of copepods in ponds fertilized with various combinations of organic and inorganic fertilizers increased a week after flooding of ponds and fertilization. Zooplankton compositions in the treatments were Apocyclops, Oithona sp., Brachionus rotundiformis, Penilia and Pseudodiaptomus sp. Copepodids and adults of Acartia tsuensis fed a mixture of algae alone or in combination with bread yeast seemed to propagate well in tank conditions. Results suggested that bread yeast could be used in combination with algae for nauplii production of Acartia in tanks. Verification runs indicated that pond-grown copepods could be used as a supplement to Artemia. Larvae fed copepods and Artemia showed similar survival rates to those fed only with Artemia. Larval survival from days 5-15 was higher in larvae reared in 20-25 ppt compared to those reared in normal seawater. 39 out of 71 tanks were discarded in 2000, whereas 3 out of 12 and 8 out of 26 production runs were aborted in 2001 and 2002, respectively. Mean survival at harvest increased from 3.06% in 2000 to 5.33 and 10.39% in 2001 and 2002, respectively. Larvae in discarded or aborted tanks were positive for viral nervous necrosis (VNN).
ArticleSubstrate preference for both burying and feeding of sandfish Holothuria scabra juveniles (3–6 g wet body weight) and their associated daily behavior, growth and survival were investigated in laboratory and field experiments using different coastal substrate types (silty mud, sandy mud, and coarse sand) to determine the ideal habitat for potential grow-out culture, sea ranching or stock enhancement of this important sea cucumber species. During the peak hours of burying (03:00–09:00 h) and feeding (15:00–03:00 h), a significantly greater number of sandfish juveniles preferred to bury in (28.3%) and feed on (21.5%) sandy mud, typical of intertidal coastal sand flats. Silty mud was the least preferred substrate for feeding (13.5%) and burying (13.8%). Burying and feeding preferences of sandfish juveniles were not significantly influenced by the presence of seagrass (Thalassia hemprichii) on coarse sand. Growth of sandfish juveniles in the first two weeks of rearing in tanks was significantly greater on coarse sand (growth rate: 0.59 g d−1 or 7.0% d−1), followed by sandy mud (0.34 g d−1 or 4.72% d−1) while OM content of these sediments remain almost unchanged. On silty mud, sandfish juveniles constantly shrunk (−0.02 g d−1 or −0.63% d−1) for 8 weeks while sediment OM content increased. In the field, silty mud substrate of a mangrove pond caused total mortality of sandfish within two weeks, while sandy mud substrate of a sand flat provided significantly higher growth than the control (no sediment), but not significantly different than coarse sand of a seagrass bed. Sandy mud to coarse sand substrates of intertidal sand flats were most preferred by sandfish juveniles while silty mud associated with muddy mangroves and culture ponds seems to be unsuitable that sandfish would opt to avoid. Our results will contribute to the selection of suitable sites for sandfish sea ranching and stock enhancement in coastal areas.