Nutrient evaluation of rotifers and zooplankton: feed for marine fish larvae (original) (raw)

Enrichment of Rotifers and Its Effect on the Growth and Survival of Fish Larvae

Rotifers, 2017

In order to improve the survival and growth of aquacultured finfish larvae, nutritional enrichment of rotifers is necessary. In the development of methodologies for material and process, n-3HUFAs especially EPA and DHA were the main focused nutrients for enrichment. Although the addition of those fatty acids to rotifer was conducted in vitro, the enrichment of DHA or EPA to phospholipid was suggested recently, as well as the optimum ratio among DHA, EPA, and arachidonic acid. On the other hand, other nutrients, e.g., taurine, vitamin A, and some minerals, have also been suggested to enrich rotifers. These mean that not only specific nutrients but also the balance among nutrients is important to enrich rotifers nutritionally and improve the performance of cultured finfishes. Moreover, the influence by rotifer culture method and protocol and the development of enrichment method should be taken into consideration for improving the efficiency of enrichment. Future studies should investigate whether rotifers can acquire all these nutrients from the balanced nutrition.

Nutritional suitability of the rotifer, Brachionus calyciflorus Pallas for rearing freshwater fish larvae

Journal of Applied Ichthyology, 1992

Brachionus calyciflorus Pallas f e l o n Dicryospbaerzum chlorelloides were investigated in batch and semicontinuous culture systems. The mean daily roduction was 57.4 and 34.2 mg of rotifers I-'&' (wet weight) respectively and were highly depen&nt o n initial algal cell density. The rotifer fed on algae contained high amounts of linoleic acid (18 : 2n-6) and amino acids such as arginine. The suitability of rotifers for gud eon Gobio gobzo L. and perch Percafluviatilis L. larvae during their early feeding stage was investigatei. After a 10-day experiment, larvae fed with rotifers grew significantly faster than those fed on micro-encapsulated dry food. The best food conversion and protein efficiency ratio were observed with the larvae fed with rotifers. Combining rotifers with micro-encapsulated dry food better improved growth rate and food utilization in perch than did the dry food alone.

Comparison of the fatty acid composition of the freshwater fish larvae Tilapia zillii, the rotifer Brachionus calyciflorus, and the microalgae Scenedesmus abundans, Monoraphidium minitum and Chlorella vulgaris in the algae-rotifer-fish larvae food chains

Aquaculture, 1999

The proximate and the fatty acid analysis of the warm freshwater fish, Tilapia zillii larvae, the freshwater rotifer Brachionus calyciflorus and the microalgae Scenedesmus abundans, Monoraphidium minitum and Chlorella Õulgaris each constituting a different food chain with B. calyciflorus and T. zillii larvae have been carried out. C. Õulgaris had significantly higher lipid content than the other two microalgae and this was also reflected in the lipid content of B. calyciflorus fed each of the microalgae separately. Five fatty acids dominated in all the microalgae, namely 18:3n y 3, 18:2 n y 6, 18:0, 18:1 and 16:0 though there were significant differences both in quantitative distribution of these acids and the total fatty acid content. The content of 18:3n y 3, 18:2 n y 6 and 16:0 and the total fatty acid content of C. Õulgaris were considerably higher than the corresponding values in the other two microalgae. But interestingly, these strong differences were not reflected in B. calyciflorus samples fed these microalgae separately though the one fed C. Õulgaris had slightly higher total fatty acid content than the other two rotifer samples. One can consider that the freshwater rotifer B. calyciflorus is capable of

Amino acid pools of rotifers and Artemia under different conditions: nutritional implications for fish larvae

Aquaculture, 2004

The rearing of most marine fish species still relies on live food. Amino acids (AA) are the building blocks for protein synthesis, are important energy substrates, and are involved in specific physiological functions. Thus, the AA pools (free and protein-bound) of the rotifer Brachionus rotundiformis and of Artemia parthenogenetica metanauplii were analysed, after enrichment with different diets or at different salinities. The changes in these pools were related to their impact when used as feed for the developing fish larvae. Rotifers and Artemia were enriched for 24 h in microalgae, in commercial diets, or starved for the same time period. The enrichment at different salinities was also tested using Artemia. The free AA (FAA) quantity and quality was strongly affected by the enrichment used, in both rotifers and Artemia metanauplii. The relative FAA content was significantly higher in rotifers and Artemia enriched with microalgae than in the ones enriched with commercial products, and between the different microalgae tested, the enrichment in T. chui resulted in the highest FAA content for both preys. Differences regarding the FAA quantity and quality were also found between rotifers and Artemia. With the exception of the starved preys, a higher relative FAA content was found in rotifers than in Artemia metanauplii and while the FAA pool of the rotifers was dominated by alanine, taurine was the dominant AA in the FAA pool of Artemia. Salinity had only a small effect on the FAA pool of Artemia. Concerning the protein fraction, starvation increased the relative protein content in the rotifers. Among the metanauplii, the relative protein content was affected neither by the enrichment nor by salinity, except for a significantly lower content found when the microalgae Nannochloropsis gaditana was used. The quality of the protein pool is affected by the different enrichments, but not by salinity. However, the changes in the protein-bound AA pool were less pronounced than for the FAA pool and reflect 0044-8486/$ -see front matter D Aquaculture 234 (2004) 429 -445 differences in the protein content and/or quality of the diet. This study showed that the AA composition of cultured zooplankton is affected by feeding regime and by salinity. The choice of the best zooplankton enrichment and/or mixture of enrichments for the different fish larval stages, should take into account the AA composition, in order to fulfil the energetic and nutritional requirements of the larvae. D

Effects of Rotifer and Artemia Fatty-Acid Enrichment on Survival, Growth and Pigmentation of Summer Flounder Paralichthys dentatus Larvae

Journal of the World Aquaculture Society, 1998

Abstracr.-Enrichment of live food for marine fish larvae with highly unsaturated fatty acids (HUFA) has been shown to improve survival, growth and stress resistance in many species and to decrease pigmentation abnormalities in flatfish. In order to aid the developing summer flounder industry, we conducted an experiment in which summer flounder larvae were fed diets differing in HUFA composition to determine whether enrichment with a commercially available product would increase survival and growth and reduce the incidence of abnormal pigmentation. We also examined whether growing unenriched rotifers on different species of algae would affect the survival, growth and pigmentation of the flounder larvae to which they were fed. Growth of summer flounder larvae was significantly better when they were fed HUFA-enriched Mtifers and Artemia rather than unenriched and, among the unenriched treatments, was significantly better when the larvae were fed rotifers raised on Isochrysis galbana rather than on Tetraselmis suecica. The percentage of larvae that failed to complete metamorphosis during the experiment was significantly higher in the unenriched treatments than in the enriched treatments. Neither survival nor percentage of individuals with pigmentation abnormalities were significantly different among the treatments.

Replacement of fresh algae with commercial formulas to enrich rotifers in larval rearing of yellowtail kingfish Seriola lalandi (Valenciennes, 1833)

Aquaculture Research, 2012

This study compared the efficacy of four products that are commonly used in hatchery for nutritional enhancement of rotifer Brachionus plicatilis as the starter food for yellowtail kingfish Seriola lalandi larvae. This experiment consisted of one fresh algae and three enrichment products: (1) Fresh algae were a mixture of Nannochloropsis and Isochrysis at 2:1 on a cell concentration basis; (2) S.presso, (Selco S.presso ® , INVE Aquaculture); (3) Algamac 3050 ® (Aquafauna, USA); (4) Nutrokol ® (Nutra-Kol, Australia). Survival rates of the fish fed rotifers enriched with fresh microalgae (40.69%) and S.presso (31.21%) were higher than those fed Algamac 3050 (10.31%). On 3 day post hatch (DPH), fish feeding incidence in the fresh algae treatment was significantly higher than that in other treatments. On 6 DPH, fish showed the lowest feeding incidence in the Algamac 3050 treatment. The methods of enrichment did not affect total lipid levels in either rotifer or fish larvae, but Algamac 3050 enrichment achieved the highest DHA/EPA ratio and lowest EPA/ARA ratio in both rotifers and fish larvae. This study indicates that fresh algae can be replaced by S.presso, but Algamac 3050 is not as good as other formula for rotifer enrichment in rearing yellowtail kingfish larvae in this system.

A review of the nutritional effects of algae in marine fish larvae

Aquaculture, 1997

In the first-feeding of larval, turbot (Scophthalmus maximus) and halibut (Hippoglossus hippoglossus), microalgae are used in the production of rotifers (Bruchionus plicatilis) in order to transfer essential nutrients from the algae to the live food. In addition, the algae may be given directly to the larvae along with the live food. In this circumstance they act both as food for the fish larvae and for the live food. Microalgal addition to the first-feeding tanks along with the rotifers improved growth and survival of larvae, whereas short-term enrichment of rotifers with algae did not improve growth and survival of larvae in tanks without algae added. The algae in larval tanks tended to modify and stabilize the nutritional quality of the rotifers in the period before they were consumed by the larvae. The lipid content and fatty acid composition of the rotifers reflected the composition of the algal diets, and the algal species used may be an effective tool to control the fatty acid content (especially DHA, 22:6n-3, docosahexaenoic acid, and EPA, 205n-3, eicosapentaenoic acid). The content of n-3 polyunsaturated fatty acids varied between algal species, and to some extent, with the growth limitation of the algal cells. Young stages of marine fish larvae ingested microalgae, but the algal cells were assimilated to a different extent in halibut and turbot. The ingested microalgae may have triggered the digestion process or contributed to the establishment of an early gut flora. The algae in larval tanks most probably modified the bacterial flora of the water and the rotifers. In addition, the algae in larval tanks may have modified the light milieu for the larvae. 0 1997 Elsevier Science B.V.

Effect of enriched rotifers on growth, survival, and composition of larval Atlantic cod (Gadus morhua)

ICES Journal of Marine Science, 2006

Recently, the nutritional requirements of marine finfish larvae have received considerable attention, and studies have shown that docosahexaenoic acid (DHA) affects the growth and survival of marine finfish larvae. We investigated the effects of different rotifer diets containing variable amounts of DHA on the growth and survival of larval Atlantic cod (Gadus morhua L.). Four different commercial rotifer enrichment formulations were used: spray-dried whole cells composed of Crypthecodinium sp. (ED1), spray-dried whole cells of Schizochytrium sp. (ED2), an oil emulsion (ED3) and ED1, and dried Chlorella at a 7:3 ratio by weight (ED4). The resultant rotifers contained a similar concentration of DHA (1.1–1.6% DW), but the level of DHA differed in proportion to EPA for each enrichment, and was designated ER1–4. Twelve 30-l aquaria were used with three replicates per treatment. Larvae were fed with rotifers from 3 to 43 days post-hatch (dph) at 4000 prey l−1. At the end of the experiment...