Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Electronic Resource  (7)
  • 2000-2004  (7)
Material
  • Electronic Resource  (7)
Years
Year
  • 1
    ISSN: 1365-2109
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A dense nitrifying culture (ABIL) has been examined for its capacity to stimulate rotifer growth in a labscale culture system. The nitrifiers were applied in different ways. When ABIL was added directly to rotifer batch cultures, it gave rise to significantly higher population densities (factor 1.5–2.5 higher, P 〈 0.05). The nitrifiers were subsequently examined for their capacity to enhance the start-up of bioreactors, commonly installed in aquaculture rearing tanks. Of the different carrier materials used in these bioreactors, i.e. CaCO3, gravel and a PVC matrix (Bionet), CaCO3 gave by far the best results. In a third set of experiments, effectively nitrifying bioreactor systems were connected to rotifer culture tanks and operated over a period of up to 10 days. It was demonstrated that the ABIL inoculated CaCO3-based bioreactor allowed excellent rotifer growth reaching rotifer densities up to 5500 rotifers per mL. Moreover, a new system in which the ABIL culture was recirculated through hollow fibres was developed and demonstrated to be effective for supporting rotifer growth up to 3500 rotifers per mL. Overall, the use of the dense nitrifying culture either in seed batch cultures, conventional bioreactors or hollow fibre bioreactor systems in support of rotifer cultures was demonstrated to be effective for improving the water quality and the rotifer growth.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Aquaculture research 33 (2002), S. 0 
    ISSN: 1365-2109
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Two series of feeding experiments were conducted to study the feasibility of using decapsulated Artemia cysts for direct feeding to ornamental fish. The first series evaluated the dietary values of the dried and the brine decapsulated Artemia cysts against two conventional live feeds, Artemia nauplii and Moina for adults and fry of the guppy, Poecilia reticulata Peters. In the second series, brine cysts were used for feeding to fry of four other important ornamental fish species, viz. platy, Xiphophorus maculatus (Günther), swordtail, X. helleri (Heckel), molly, P. sphenops Cuvier & Valenciennes and black neon tetra, Hyphessobrycon herbertaxelrodi Géry, and the results were compared with those fed Moina. Evaluation of the performance of the fish fed the various diets was based on stress resistance, growth and survival of the fish. Our findings indicated that decapsulated cysts could be used as a substitute for Artemia nauplii or Moina in freshwater ornamental fish culture. Apart from being a hygienic off-the-shelf feed, the direct use of the cysts also signifies a new area of application for low-hatch cysts in the ornamental fish industry, with concomitant saving in feed costs.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1365-2109
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Two experiments were carried out to determine the quantitative lipid requirements for ovarian maturation of Litopenaeus vannamei (Boone) broodstock. The first experiment tested the effect of total dietary lipid (TDL) levels of 8.1%, 8.8%, 9.8% and 11.2% on the gonadosomatic index (GSI), hepatosomatic index (HSI), survival and body weight. The second experiment tested the effect of total dietary levels of highly unsaturated fatty acids (TDH) 0.6%, 1.3%, 2.0% and 2.7% on the same parameters mentioned above and on the haemolymphatic vitellogenin (vg) concentration. The GSI was higher in females fed 8.1% TDL as compared with those fed 8.8% TDL (P ≤ 0.05), and higher in females fed 8.1% and 8.8% TDL than in those fed 9.8% and 11.2% TDL. Increasing TDH levels led to increasing levels of highly unsaturated fatty acids (HUFA) in the ovaries (r2 = 0.999). However, the GSI was not affected by dietary treatments (P 〉 0.05). The vg concentration was higher in animals receiving 2.0% TDH as compared with those receiving 2.7% TDH. In conclusion, high TDL levels affected ovarian maturation in a negative way, why TDH levels had no pronounced effect on ovarian maturation within the range tested in this study.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Verlag GmbH
    Journal of applied ichthyology 19 (2003), S. 0 
    ISSN: 1439-0426
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Burbot Lota lota L. is one of the endangered freshwater fish species in western Europe for which the development of controlled larval rearing procedures could produce enough material for stock enhancement. The suitability of the freshwater rotifer Brachionus calyciflorus as a start food for larviculture of burbot was investigated. After yolk-absorption, the larvae were stocked in 40-L tanks under different feeding conditions: clear water rearing conditions with rotifers (Brachionus calyciflorus) for 10 days (R), green water conditions (Chlorella sp.) with rotifers offered for 10 days (MALR), green water conditions (Chlorella sp.) for 3 days followed by clear water in combination with rotifer feeding for 7 days (AL3R), and clear water conditions with Artemia nauplii offered for 10 days (Art). After the 10-day feeding, all groups received Artemia nauplii up to 35 days post-hatching. Larval survival was counted at day 10 and at the end of the 35-day rearing experiment. At day 35, a significant survival difference was noted between the groups where rotifers were supplemented with algae vs only Artemia. At the end of the experiment, the highest survival rate (69.20%) was obtained with larvae receiving only algae in the first 3 days of feeding. Lowest survival rate (24.90%) was obtained with larvae receiving only Artemia for 35 days. This indicates that smaller prey are essential for burbot at first feeding. Larval length and wet weight were measured at the time of mouth opening, at days 7, 10, and 21, and at the end of the experiment (day 35). On day 35, mean length of the larvae varied significantly between the treatments. However, the final wet weight of the larvae did not vary significantly between the treatments.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1365-2095
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: In the first experiment, conducted in a research facility, Litopenaeus vannamei broodstock were fed either a 100% fresh food control treatment (FRE, consisting of frozen squid, oyster, mussel and enriched Artemia biomass in a 2.3:1.4:1.3:1 dry matter ratio) or one of the two treatments in which 50% [dry matter (DM)] of the fresh food was substituted with experimental artificial diets: a dry diet based on freeze-dried Artemia biomass (ART) and a control dry diet (CON). In the second experiment, conducted in a commercial hatchery, shrimp broodstock were fed either a fresh ration (FRE, consisting of frozen squid, polychaetes and enriched Artemia biomass in a 2.5:1.5:1 DM ratio) or the same experimental artificial diets (ART and CON) replacing 50% of the DM by elimination of polychaetes and Artemia biomass. In experiment 1 treatments CON and ART produced better results (P=0.05) than treatment FRE in terms of spawn performance and egg production per female. In experiment 2 no differences were detected among treatments FRE and CON whereas treatment ART performed better (P=0.05) in terms of spawning, egg production per female and spermatophore quality. Broodstock survival and offspring quality did not differ between treatments in either experiment.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  Free amino acid (FAA) and protein content were measured in various developmental stages of Artemia franciscana, from cysts to Instar III metanauplii. In addition, decapsulated cysts of 15 Artemia populations from different localities were compared with respect to their FAA and protein content. Furthermore, the content and composition of the FAA pool were modulated by hatching the cysts at various salinities, and by enriching the nauplii with algae or a lipid-enrichment emulsion. The FAA content increased threefold from cysts to nauplii, and Instar III metanauplii contained nearly 50% taurine of total FAA. Cysts of A. franciscana were found to contain one-third the amount of FAA compared to the other Artemia species investigated. The content and pool composition of FAA was successfully modulated in 11 of 13 populations, where by the content of FAA was significantly increased when hatched at high salinity. Finally, enrichment elevated the content of FAA and changed the pool composition, thereby showing a dietary effect. Algal enrichment also increased the protein content.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The present study evaluated the effect of starvation and of feeding various algal and lipid-supplemented diets on the lipid content and lipid class distribution in the polar and neutral lipids of early juvenile oysters (Crassostrea gigas) and clams (Tapes philippinarum L.). T. philippinarum was starved, fed a mixed algal diet [Tetraselmis suecica and Isochrysis galbana (clone T-Iso)] or solely T. suecica at three different feeding rations, either supplemented or not supplemented with lipid emulsions. C. gigas was fed T. suecica with and without the supplementation of lipid emulsions or liposomes. When T. philippinarum and C. gigas were fed solely T. suecica, no qualitative and only minor quantitative differences were observed between the lipid class profile of both species. The major neutral lipids were triglycerides (TAG) and free sterols plus diglycerides (FS+DAG), whereas the polar lipids were dominated by phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol plus ceramideaminoethanol phosphonate (PI+CAEP). An increase of the algal feeding ration resulted in an increase of the lipid content of spat which was associated with a significant augmentation of the TAG level (as percentage of the total lipids and as percentage of the neutral lipids). Lipid supplementation evoked a similar though more pronounced effect. Starvation resulted in a significant decline of the lipid content and a complete depletion of the TAG reserve. Contrary to the neutral lipids (NL), the relative proportion (percentage of total polar lipids, PL) of the individual PL classes was hardly affected by the diet. The importance of lipid and TAG reserves in early juveniles is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...