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Abdolsamad Jahangard - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of Free-Living Nematode Panagrellus Redivivus as a Live Food Organism for Silver Barb Barbodes Gonionotus Larvae
2003Co-Authors: Abdolsamad JahangardAbstract:A series of experiments were conducted to develop mass production and improve nutritional quality of free-living nematode Panagrellus redivivus. The performance of nematodes P. redivivus produced on different culture media on growth and survival of silver barb Barbodes gonionotus larvae were also studied. Prior to evaluation of P. redivivus as a larval live Food Organism, a study was conducted on the optimal stocking density of B. gonionotus larvae. Best larval growth and survival were obtained at 10 larvae L-1 for a 16-days rearing period. However, a range of 34-65 larvae L-1 was recommended for its commercial hatchery production. A comparative study on performance of nematode, rotifer, Moina and Artemia was carried out. B. gonionotus larvae fed with Artemia and nematode exhibited significantly (PO.05) effect on the biochemical composition and nutritional value of P. redivivus for silver barb P. gonionotus larvae. Another study was conducted to determine the effect of lipid enrichment on the production of P. redivivus. The results showed that the best lipid enrichment level for the maximum production of P. redivivus was 3.43%. The extremely low production of P. redivivus in unenriched medium suggested that lipid has an important role in reproduction, metabolism and as the main energy source. The results of a feeding trial showed that nematodes grown in media enriched with> 2.6% oil level were unsuitable for silver barb B. gonionotus larvae.
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evaluation of free living nematode panagrellus redivivus as a live Food Organism for silver barb barbodes gonionotus larvae
2003Co-Authors: Abdolsamad JahangardAbstract:A series of experiments were conducted to develop mass production and improve nutritional quality of free-living nematode Panagrellus redivivus. The performance of nematodes P. redivivus produced on different culture media on growth and survival of silver barb Barbodes gonionotus larvae were also studied. Prior to evaluation of P. redivivus as a larval live Food Organism, a study was conducted on the optimal stocking density of B. gonionotus larvae. Best larval growth and survival were obtained at 10 larvae L-1 for a 16-days rearing period. However, a range of 34-65 larvae L-1 was recommended for its commercial hatchery production. A comparative study on performance of nematode, rotifer, Moina and Artemia was carried out. B. gonionotus larvae fed with Artemia and nematode exhibited significantly (P
Jan Ove Evjemo - One of the best experts on this subject based on the ideXlab platform.
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Copepods as live Food Organisms in the larval rearing of halibut larvae (Hippoglossus hippoglossus L.) with special emphasis on the nutritional value
Aquaculture, 2003Co-Authors: Jan Ove Evjemo, Kjell Inge Reitan, Yngvar OlsenAbstract:In the natural Food web, zooplankton constitutes a major part of the diet for marine fish larvae and it is generally believed that copepods can meet the nutritional requirements of fish larvae. In this study, different copepod species were analysed for total lipid content, fatty acid and protein content and used in first feeding experiments with halibut larvae (Hippoglossus hippoglossus L.) together with enriched nauplii and juvenile stages of Artemia franciscana. Special attention was paid to the DHA content in both the live Food Organisms and the fish larvae. Copepodid and adult stages of the marine copepods Temora longicornis and Eurytemora sp. had a total lipid content varying between 7% and 14% of dry weight (DW). Copepodid stages I, II and III of Calanus finmarchicus had a lipid content varying between 10% and 19% of DW, increasing to 22–25% in copepodid stages IV, V and the adult stages. The predominant fatty acids of all copepods were docosahexaenoic acid (DHA; 22:6n−3), eicosapentaenoic acid (EPA; 20:5n−3) and the saturated fatty acid 16:0. In T. longicornis and Eurytemora sp. DHA constituted 26–42%, EPA 15–24% and 16:0 8–12% of total fatty acids. In C. finmarchicus, the DHA content ranged between 21% and 32.5%, whereas the content of EPA and 16:0 was 15–21% and 9–15% of total fatty acids, respectively. The sum of n−3 HUFA was highest in T. longicornis and Eurytemora sp. (55–62% of total fatty acids) and lowest in C. finmarchicus (38–47%). The loss rate (% day−1) of the total lipid and fatty acid content during starving conditions was 18 and 24% day−1 in T. longicornis, and 12 and 16% day−1 in Eurytemora sp., respectively. In both copepods, the relative content of DHA (% of total fatty acids) increased with time during starvation, reaching 43% in T. longicornis and 49% in Eurytemora sp. The quantitative content of DHA decreased steadily although at a lower rate than that of other fatty acids. The protein content of various copepods varied between 52.4% and 57.6% of dry weight (DW), and was significantly higher than in A. franciscana (41% in newly hatched nauplii and 34% after 24-h enrichment). There was a close relationship between the percent DHA content in 28–36-day-old halibut larvae and the live Food Organisms they were fed on. High percent DHA content in the live Food Organism resulted in a high percent DHA content in the fish larvae and vice versa. The relatively high DHA content in the larvae was significantly reduced after 8 days when given enriched A. franciscana. For the rest of the feeding period, the DHA content decreased steadily when fed on A. franciscana, whereas it remained at the initial high level in larvae-fed copepods.
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Production and nutritional adaptation of the brine shrimpArtemia sp. as live Food Organism for larvae of marine cold water fish species
2001Co-Authors: Jan Ove EvjemoAbstract:High nutritional value of Artemia sp. refers to high content of highly unsaturated fatty acids (n-3 HUFA) and in particular the content of DHA. In the enrichment experiments presented in this thesis new diets and one new Artemia species was introduced, and the lipid and fatty acid content in Artemia nauplii was followed during enrichment. Post enrichment the stability of the nutritional value was determined at different temperatures. In order to establish and optimise the feeding regimes for marine fish larvae, by introducing juvenile and older stages of Artemia sp., feeding rate and growth rate was determined when Artemia franciscana was grown from nauplius to pre-adult stage.To meet the nutritional requirements of the fish larvae enrichment relative to larval requirements of the natural Food sources was evaluated. Copepods and Artemia nauplii, live Food Organisms with different DHA content, was used in first feeding experiments with halibut larvae (H. hippoglossus) to examine how this influenced the DHA content of the larvae. Based on lipid and protein analysis of marine copepods these Organisms can be used as a nutritional reference in order to establish, and further improve, the nutritional value of Artemia sp. as live Food Organism.
Wolfgang Engelmann - One of the best experts on this subject based on the ideXlab platform.
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thalassomyxa australis rhythmicity v synchronization by light dark cycles depends on temperature and Food Organism
Biological Rhythm Research, 1991Co-Authors: Brigitta Landsbeck, Wolfgang EngelmannAbstract:Abstract Silyn‐Roberts (1988) reported that synchronization of Thalassomyxa australis by light‐dark‐cycles (LD) occurred when Dunaliella was used as a Food Organism, whereas the use of Amphiprora as a Food Organism lead to freerunning rhythmic changes between active and resting phases in this marine rhizopod. We have found, however, that synchronization to LD cycles also depends on ambient temperature and can occur with Amphiprora as a Food Organism at higher temperatures (19.5°C) than used by Silyn‐Roberts (18.5°C). At lower temperatures (16.5°C) both, Amphiprora ‐ and Dunaliella‐fed Thalassomyxa australis cannot be synchronized by the LD‐cycle. The difference in synchronization of Thalassomyxa australis in connection with the two Food Organisms is restricted to a small temperature range between 17.3 and 19.2°C. Under freerunning conditions the period length of Am‐phiprora‐fed Thalassomyxa australis depends more strongly on temperature than that of Dunaliella‐fed cultures. Period length of Dunaliella‐fed...
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Thalassomyxa australis rhythmicity V. synchronization by light‐dark‐cycles depends on temperature and Food Organism
Journal of Interdisiplinary Cycle Research, 1991Co-Authors: Brigitta Landsbeck, Wolfgang EngelmannAbstract:Abstract Silyn‐Roberts (1988) reported that synchronization of Thalassomyxa australis by light‐dark‐cycles (LD) occurred when Dunaliella was used as a Food Organism, whereas the use of Amphiprora as a Food Organism lead to freerunning rhythmic changes between active and resting phases in this marine rhizopod. We have found, however, that synchronization to LD cycles also depends on ambient temperature and can occur with Amphiprora as a Food Organism at higher temperatures (19.5°C) than used by Silyn‐Roberts (18.5°C). At lower temperatures (16.5°C) both, Amphiprora ‐ and Dunaliella‐fed Thalassomyxa australis cannot be synchronized by the LD‐cycle. The difference in synchronization of Thalassomyxa australis in connection with the two Food Organisms is restricted to a small temperature range between 17.3 and 19.2°C. Under freerunning conditions the period length of Am‐phiprora‐fed Thalassomyxa australis depends more strongly on temperature than that of Dunaliella‐fed cultures. Period length of Dunaliella‐fed...
Rho Sum - One of the best experts on this subject based on the ideXlab platform.
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Survival and Growth Responses on Jumping of the Each Saline Concentrations of Freshwater Cladoceran Moina macrocopa and Estuarine Cladoceran Diaphanosoma celebensis
Korean Journal of Fisheries and Aquatic Sciences, 2001Co-Authors: Jung Min-min, Kim Hyeung-sin, Rho SumAbstract:In this study, we investigated that the survival and growth responses of freshwater cladoceran Moina macrocopa and estuarine cladoceran Diaphanosoma celebensis on the saline culture conditions after transferring for using as live Food Organism. Estuarine cladoceran D. celebensis was survived and grew on the all salines except to saline jump culture condition of 0 ppt. However, freshwater cladoceran M. mcrocopa was died or decline on the over saline jumping culture conditions of 4 ppt within 5 minutes. These suggest the possibility of using the estuarine cladoceran D. celebensis compare with freshwater cladoceran M. macrocopa as a substitute live Food Organism for Artemia in the marine larval rearing.
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Selection of Culture Scale for Stable Culture of an Estunrine Cladoceran Diaphanosoma celebensis
Korean Journal of Fisheries and Aquatic Sciences, 1999Co-Authors: Jung Min-min, Kim Hyeung-sin, Rho SumAbstract:Cladocera are important Food Organism for seed production of finfishes. freshwater cladocera such as Daphnia and Moina are well known Food Organisms for the larval rearing of freshwater fishes and are easy for mass culture. However, mass culture technique for marine cladocera are not yet developed, The only mass produced Food Organisms available these days for the larval production of marine finfishes are rotifer and Artemia. An estuarine cladoceran, Diaphanosoma celebensis, has a high possibility of being used as a Food Organism for the larval rearing of marine finfishes because this species is much easier to mass culture than marine ones. Therefore many studies are needed for this species. In this study, the effects of the volumes of culture container, 40, 1,500 and 15,000 ml, on the stable production of this species were tested and results are as follow: The maximum densities of this species in each of the culture volumes were reached after 14 days in 40 ml, 12 days in 1,500 ml, and 21 days in 15,000 ml with values of 3.4 0.4, 14.2 2.1 and 2.5 1.6 per ml, respectively. The relative population growth index (RPGI) was stable in the culture volume of 1,500 ml. Moreover, possible harvesting number(individual/ml/day) was much higher in the 1,500 ml container than the other culture volumes. Therefore, optimum culture volume among the tested volumes for mass production of this species was 1,500 ml.
Yngvar Olsen - One of the best experts on this subject based on the ideXlab platform.
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Copepods as live Food Organisms in the larval rearing of halibut larvae (Hippoglossus hippoglossus L.) with special emphasis on the nutritional value
Aquaculture, 2003Co-Authors: Jan Ove Evjemo, Kjell Inge Reitan, Yngvar OlsenAbstract:In the natural Food web, zooplankton constitutes a major part of the diet for marine fish larvae and it is generally believed that copepods can meet the nutritional requirements of fish larvae. In this study, different copepod species were analysed for total lipid content, fatty acid and protein content and used in first feeding experiments with halibut larvae (Hippoglossus hippoglossus L.) together with enriched nauplii and juvenile stages of Artemia franciscana. Special attention was paid to the DHA content in both the live Food Organisms and the fish larvae. Copepodid and adult stages of the marine copepods Temora longicornis and Eurytemora sp. had a total lipid content varying between 7% and 14% of dry weight (DW). Copepodid stages I, II and III of Calanus finmarchicus had a lipid content varying between 10% and 19% of DW, increasing to 22–25% in copepodid stages IV, V and the adult stages. The predominant fatty acids of all copepods were docosahexaenoic acid (DHA; 22:6n−3), eicosapentaenoic acid (EPA; 20:5n−3) and the saturated fatty acid 16:0. In T. longicornis and Eurytemora sp. DHA constituted 26–42%, EPA 15–24% and 16:0 8–12% of total fatty acids. In C. finmarchicus, the DHA content ranged between 21% and 32.5%, whereas the content of EPA and 16:0 was 15–21% and 9–15% of total fatty acids, respectively. The sum of n−3 HUFA was highest in T. longicornis and Eurytemora sp. (55–62% of total fatty acids) and lowest in C. finmarchicus (38–47%). The loss rate (% day−1) of the total lipid and fatty acid content during starving conditions was 18 and 24% day−1 in T. longicornis, and 12 and 16% day−1 in Eurytemora sp., respectively. In both copepods, the relative content of DHA (% of total fatty acids) increased with time during starvation, reaching 43% in T. longicornis and 49% in Eurytemora sp. The quantitative content of DHA decreased steadily although at a lower rate than that of other fatty acids. The protein content of various copepods varied between 52.4% and 57.6% of dry weight (DW), and was significantly higher than in A. franciscana (41% in newly hatched nauplii and 34% after 24-h enrichment). There was a close relationship between the percent DHA content in 28–36-day-old halibut larvae and the live Food Organisms they were fed on. High percent DHA content in the live Food Organism resulted in a high percent DHA content in the fish larvae and vice versa. The relatively high DHA content in the larvae was significantly reduced after 8 days when given enriched A. franciscana. For the rest of the feeding period, the DHA content decreased steadily when fed on A. franciscana, whereas it remained at the initial high level in larvae-fed copepods.