Enrichment of Rotifers and Its Effect on the Growth and Survival of Fish Larvae (original) (raw)
Related papers
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.
Nutrient evaluation of rotifers and zooplankton: feed for marine fish larvae
Aquaculture Nutrition, 2013
The objective of this study was to examine the biochemical composition of intensively reared rotifers after enrichment with three commonly used enrichment media, Multigain, Ori-Green and DHA-enriched freshwater algae Chlorella, using standard enrichment protocols at a local cod larvae producer and compare it with that of natural zooplankton from Lofilab AS, a cod larvae producer using semi-intensive rearing techniques. Unenriched rotifers were analysed to examine whether the enrichment procedures were successful in increasing the content of essential nutrients to level requirements for marine fish larvae. Neither total lipids nor proteins were affected by enrichment. Unenriched rotifers were significantly lower in highly unsaturated fatty acids (HUFAs) and significantly higher in linoleic acid (LA, C18:2, n-6), than were zooplankton. Enrichment with Chlorella and Multigain increased the HUFAs significantly, while they were slightly reduced after enrichment with Ori-Green. Total amino acids and mineral content were unaffected by enrichment. Zooplankton was rich in taurine and selenium, whereas rotifers were devoid of it, both prior to and after enrichment. Using zooplankton as a reference for the nutritional requirements of marine fish larvae, results from this study demonstrate that enrichment media currently in use are not effective for enhancing the nutritional quality of rotifers.
Rotifers as food in aquaculture
Hydrobiologia, 1989
The rotifer Brachionusplicatilis (O.F. Muller) can be mass cultivated in large quantities and is an important live feed in aquaculture. This rotifer is commonly offered to larvae during the first 7-30 days of exogenous feeding. Variation in prey density affects larval fish feeding rates, rations, activity, evacuation time, growth rates and growth efficiencies. B. plicatilis can be supplied at the food concentrations required for meeting larval metabolic demands and yielding high survival rates. Live food may enhance the digestive processes of larval predators. A large range of genetically distinct B. plicatilis strains with a wide range of body size permit larval rearing of many fish species. Larvae are first fed on a small strain of rotifers, and as larvae increase in size, a larger strain of rotifers is introduced. Rotifers are regarded as living food capsules for transferring nutrients to fish larvae. These nutrients include highly unsaturated fatty acids (mainly 20: 5 n-3 and 22: 6 n-3) essential for survival of marine fish larvae. In addition, rotifers treated with antibiotics may promote higher survival rates. The possibility of preserving live rotifers at low temperatures or through their resting eggs has been investigated.
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...
Journal of The World Aquaculture Society, 2008
The effect of enriching rotifer prey with highly unsaturated fatty acids on sunshine bass Morone chrysops × M. saxatilis larval survival and growth from ages 4 to 12 d posthatch was determined. Comparisons were made among larvae fed (1) rotifers cultured with Nannochloropsis paste versus rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000; (2) no rotifers versus rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000; and (3) rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000, rotifers cultured with Nannochloropsis and Pavlova pastes and enriched with Culture Selco 3000, and rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000 and Super Selco. The only differences in survival were unfed larvae with practically no survival compared to 55.4% survival for larvae fed rotifers cultured with paste plus Culture Selco 3000. Larvae fed rotifers cultured with paste plus Culture Selco 3000 were longer and had greater condition than those fed rotifers cultured with paste. Additional enrichment with Pavlova sp. or Super Selco had no affect. A canonical analysis of fatty acid contents of diets, rotifers, and fry supported evidence from harvest results. Distances between centroids indicated distinct differences among diets, less distinction among the rotifers, and little difference among fry. Enrichment enhanced growth, but additional enrichment beyond that done during rotifer culture did not increase survival, growth, or condition.
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.
Aquaculture Research, 2008
A feeding experiment was conducted to evaluate the e¡ect of rotifers (Brachionus plicatilis) and Artemia sp. enriched di¡erently on early growth, survival and lipid class composition of Atlantic cod larvae (Gadus morhua). Rotifers enrichments tested were: (1) Alga-Mac 2000 s , (2) AquaGrow s Advantage and (3) a combination of Pavlova sp. paste and AlgaMac 2000 s. The same treatments were tested with Artemia as well as a combination of DC DHA Selco s and AlgaMac 2000 s as a fourth treatment. After rotifer feeding, the larvae from treatment 3 [1.50 AE 0.11mg dry weight (dw)] were signi¢cantly heavier than larvae from treatment 2 (1.03 AE 0.04 mg dw). After feeding Artemia, the larvae from treatment 1 were signi¢cantly heavier (12.06 AE 2.54 mg dw) than those from treatments 3 (6.5 AE 0.73 mg dw) and 4 (5.31 AE 1.01mg dw). Treatment 3 resulted in the best survival through the 59 days of larviculture. After rotifer feeding, high larval concentrations of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), arachidonic acid (AA) and o 6 docosapentaenoic acid (o6DPA) could be linked to better larval growth and survival while after feeding Artemia, high larval DHA/EPA ratios ($ 3) and high DPA/ AA ratios (41) could be linked to better survival.
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.
Indian Journal of Fisheries, 2017
The present study, evaluated the effect of enrichment of the rotifer Brachionus plicatilis with the microalga Nannochloroposis salina, amino acid derivative L-carnitine and commercially available S-presso (SELCO). The study also evaluated the effect of enriched rotifers in larval rearing of Amphiprion clarkii in terms of metamorphosis, pigmentation, growth and survival of larvae.. Rotifer production increased by 43, 39 and 54% respectively in B. plicatilis enriched with different concentrations of L-carnitine at 1, 10 and 100 mg l-1 on day 4 (p<0.001) in comparison with the control group maintained on algal diet alone. Total unsaturated fatty acid (PUFA, HUFA and n-3 fatty acids) and the ratios of n-3/ n-6, DHA/EPA, EPA/AA were significantly higher (p<0.05) in the L-carnitine treated rotifers compared with the S-presso enriched as well N. salina enriched groups. Larvae of A. clarkii, fed with L-carnitine enriched rotifer achieved maximum growth of 56.92±0.2 mg; whereas, those fed S-presso treated rotifers attained only 48.74±1 mg. In L-carnitine enrichment; metamorphosis of clown fish larvae took only 10 days, while it took 11 days and 10 days respectively in S-presso and N. salina enrichment. In L-carnitine and S-presso enrichments, initial pigmentation of larvae was observed within first 3-4 days of culture, whereas it took 4-5 days in N. salina enrichment. L-carnitine enrichment resulted in the highest survival of 70%, followed by N. salina with 68% and S-presso enriched group with 52%. The results indicate that L-carnitine could be a recommendable enrichment for increasing rotifer production as well as for clown fish larval culture.
Aquaculture Research, 1996
The efficiency of the rotifer Brachionus calyciflorus Pallas as a nutritional soitrce for rearing larvae was studied in a coldwater cyprinid, the gudgeon Gobio gobio (L,), and in a percid, the perch Perca fluviatilis L., through their composition in fatty acids. Rotifer intake affected the fatty acid profiles of the larvae significantly, with an especially remarkable presence of the linoleic family. In gudgeon fed with rotifers, the polyunsaturated fatty acids (PUFA) reached 10,98% of the dry weight of the sample. This rate was highly influenced by the presence of the acids C18:2n-6 and C22:6n-3 which represented 66% of the total PUFA, In perch fed exclusively with rotifers, the PUFA represented 7,27% of the dry weight. In both cases, the ratio n-3/n-6 decreased by 75% and 73% after 10 days of feeding with B, calyciflorus. This variation was probably due to the exogenous supply in acids of the linoleic family through the rotifers and to the fact that these two species of fish seem to favour the mobilization of the n-3 PUFA such as C22:6n-3 for growth and survival. Moreover, with the utilization of rotifers, the reactions of elongation and desaturation from the C18;2n-6 and C18:ln-9 seemed to be much more important in the larvae. Lastly, the transition from a diet based on rotifers to one made up exclusively of frozen Artemia nauplii led to a significant reduction of fatty acids in fish. It reached 60,2% and 26,5% of the total fatty acids in the gudgeon and perch, respectively, and was observed especially at the level of the PUFA, On the other hand, a slight increase of the ratio n-3/n-6 was pointed out in the perch fed a mixed diet (co-feeding with rotifers and dry food), a phenomenon probably due to the reduction of C18:2n-6 in the larvae.