Optimal first feed organism for South African mud crab <Emphasis Type="Italic">Scylla serrata</Emphasis> (Forskål) larvae

It is not known whether rotifers or Artemia nauplii are the best first food for South African mud crab Scylla serrata larvae. In order to test this, larvae were fed with five different test diets. These were rotifers for the first 8 days and newly hatched EG^® type Artemia nauplii (San Francisco Bay) from day 6 onwards (treatment R6A); newly hatched EG^® type Artemia nauplii throughout the rearing period (treatment EG); newly hatched Vinh-Chau strain (Vietnam) Artemia nauplii throughout the rearing period (treatment VC); decapsulated cysts of EG^® type Artemia throughout the rearing period (treatment DECAP); or decapsulated cysts supplemented with low densities of Artemia EG type Artemia nauplii (treatment MIX). Two experiments were conducted approximately 1 month apart using larvae from two different female crabs. Although results showed it is possible to rear S. serrata larvae through metamorphosis on Artemia nauplii exclusively, larval performance (development, survival and successful metamorphosis) was enhanced by the inclusion of rotifers as a first feed.No significant difference in performance was recorded between larvae fed on the two strains of Artemia nauplii. Larvae fed on decapsulated cysts in treatments DECAP and MIX performed poorly, but there were indications that decapsulated cysts and other inert diets may have potential as supplements to live food in the rearing of S. serrata larvae.     

Review of the present knowledge of rearing whitefish (Coregonidae) larvae

Intensive fishing of whitefish (Coregonus lavaretus) and a survival rate of the early stages of the fry that is generally too low lead, at present, to the whitefish stocks not being able to utilize fully the natural food resources now produced many times in excess of the requirements by the eutrophication of lakes.Feeding experiments in aquaria have, for several years, shown very impressively, that there are two main reasons for the high mortality of the larvae in the natural environment: high sensitivity to even a short-term lack of food and specific food requirements — the necessity for the larvae to feed on the juvenile stages of certain zooplanktonic crustaceans.Artificial breeding of whitefish eggs in cold water at 1°C caused a delay in hatching of about 8 weeks compared with natural hatching, thus allowing the release of the larvae at a time when the density of zooplankton is about ten times higher and mainly juvenile stages of crustaceans needed by the whitefish larvae are present. Hence, this is one proven way of improving the survival rate of whitefish larvae in the natural environment.Young fish, after metamorphosis, have less specialized food requirements than the larval stage and can even be fed adequately with dry food. In rearing the larvae, natural zooplankton can be replaced by the nauplii of the brine shrimp, Artemia salina. Larvae have not yet been reared on dry food or even on slowly frozen zooplankton or Artemia, but Artemia nauplii shock-frozen in liquid nitrogen (at ?196°C) were found to be as acceptable as living ones and allowed metamorphosis of the larvae to take place. The substance, assumed to be present in the living Artemia, which was lost on slow-freezing but retained after shock-freezing and was shown to be essential to the whitefish larvae, was insoluble in water. Biochemical investigation and identification of this substance are urgently required in order to synthesize an artificial complete food for whitefish larvae.As long as this artificial food is not available, attention will have to be focussed on rearing the larvae in natural ponds where the specific and essential zooplankton can be encouraged.     

Larval rearing of African carp,Labeo parvus Boulenger, 1902 (Pisces: Cyprinidae), using live food and artificial diet under controlled conditions

This study aimed at (1) evaluating the efficacy of live food organisms (Artemia and natural zooplankton) and an artificial diet in the larval rearing of African carp Labeo parvus and (2) determining appropriate rearing conditions. After yolk sac resorption, the larvae were separated into five different feeding trials with two replicates. At the end of the larval rearing period (28 days post‐hatching), the highest (94.6%) and the lowest (53.7%) cumulative survival rates were found when larvae were fed with natural zooplankton for 7 days followed by Nippai food for 21 days, and when larvae were fed from the beginning of exogenous feeding with Nippai food only respectively. The significant highest body weight (351.6 mg), total length (34.4 mm) and specific growth rates (15.5%day^?1) were recorded when the larvae were fed with Artemia nauplii for 14 days followed by Nippai food for 14 days. The lowest growth performance (body weight and specific growth rates) were obtained when larvae were fed exclusively Nippai food. These results indicate that L. parvus can be successfully cultured in indoor nursery systems from hatching to the early juvenile stage.     

Survival of blue king crab Paralithodes platypus Brandt, 1850, larvae in cultivation: effects of diet, temperature and rearing density

Blue king crab (Paralithodes platypus) larvae were cultivated to test the effects of diet, temperature and rearing density. Dietary treatments included no feeding (unfed), Artemia nauplii enriched with diatoms Thalassiosira nordenskioeldii (THAL), unenriched Artemia fed in addition to Thalassiosira (A+THAL) and a control diet of Artemia enriched with frozen Isochrysis paste (ISO 6). Trials were conducted at 6 °C, and a rearing density of 10 zoea L^?1, with six replicates per treatment. The ISO 6 diet was also tested at 3 °C (ISO 3) and 9 °C (ISO 9), and at densities of 20 (ISO 20) and 40 (ISO 40) zoea L^?1. Survival of zoea larvae fed the A+THAL diet (91.7%) was significantly higher than all others, whereas unfed zoea larvae died within 2 weeks. Temperature and rearing density had no significant effects on survival. Time required to reach stage C1 was significantly greater at 3 °C (109 days) than at 6 °C (70 days), but did not decrease further at 9 °C. After reaching the postlarval (glaucothoe) stage, half of the replicates in the ISO 20 and ISO 40 treatments were fed continuously, but survival did not differ significantly from unfed glaucothoe. We conclude that blue king crab larvae are not lecithotrophic and can be cultivated with high survival using the proper diet. These techniques can be used to produce large numbers of juvenile crab for laboratory research, or could be modified for use in stock‐enhancement programmes.     

Histological evaluation of the elimination of Artemia nauplii from larval rearing protocols on the digestive system ontogeny of shi drum (Umbrina cirrosa L.)

The influence of the absence of Artemia nauplii from larval diet protocols on growth and digestive system ontogeny was studied using histological techniques in the shi drum (Umbrina cirrosa). One group of larvae was reared using the standard intensive rearing protocol, which offers a combination of enriched rotifers (Brachionus plicatilis), Artemia spp. nauplii and artificial diet (Std-group). Another group was reared using the same protocol, but without the offering of Artemia nauplii (group No-Artemia). The ontogenesis of the digestive system from hatching to metamorphosis was a very rapid process, and there were no differences between the two feeding regimes in the temporal appearance of the various components of the digestive system. The first organised presence of the hepatic and pancreatic tissue appeared at 2–3 d after hatching (dah), suggesting that these organs function from a very early developmental stage. In the No-Artemia larvae between 13 and 29 dah there was a reduction in the height of enterocytes in the intestinal mucosa, a progressive flattening of the primary intestinal folds in the anterior and posterior intestine and a decrease in lipid stores in the liver, suggesting a period of relative starvation. However, by the end of the study at 41 dah, there were no significant differences in body length, intestinal morphology or liver lipid stores between larvae reared under the two feeding regimes. The study suggests that the diet may influence the maturation and/or function, but not the ontogeny of the digestive system. Furthermore, the rapid differentiation of the digestive system in shi drum and the prompt recovery of the No-Artemia larvae from the symptoms of starvation by 29 dah, indicate a plasticity during ontogenesis and the ability of larvae to adapt to artificial diets at very early developmental stages.     

Use of commercial Artemia replacement diets in culturing larval American lobsters (Homarus americanus)

This work reports on the successful incorporation of commercial formulated Artemia replacement diets as 50% of a larval American lobster diet. Combination diets of either live Artemia nauplii or frozen adult n-3 fatty acid enriched Artemia with a rotation of three commercial formulated diets resulted in equivalent survival to stage IV (19–25%), postlarval size and subsequent early juvenile performance compared to an Artemia nauplii plus frozen Artemia combination diet. A 100% formulated diet resulted in reduced larval survival (6%) and postlarval size, while a larval diet of 100% frozen adult Artemia resulted in reduced postlarval quality and early juvenile performance. The much lower price of the formulated diets compared to the prices of Artemia nauplii and frozen Artemia makes its inclusion in the lobster larval diet the most cost-effective diet choice.     

Substance essential for metamorphosis of fish larvae extracted from Artemia

Up to now the larval stages of fishes could not be reared successfully past metamorphosis when fed exclusively upon dry food. In rearing whitefish larvae, living Artemia nauplii could be replaced by shock-frozen ones (at ?196°C). This suggested that a substance essential for the whitefish larvae is present in living Artemia and preserved during rapid shock freezing. This substance seemed to be insoluble in water. It could be dissolved and extracted from the nauplii by acetone and could be transferred to a dry food. This enriched dry food offered to the whitefish larvae enabled them to grow up to and past metamorphosis successfully.     

黑点青鳉的生长和摄食行为发育

针对黑点青鳉实验室养殖成活率低的问题,对其摄食行为发育进行研究,了解其早期阶段的摄食行为发育状况,为人工养殖提供理论依据。通过单摄像机结合镜面成像的方法,对黑点青鳉胚后发育阶段90 d摄食行为的观察与分析,研究了投喂卤虫无节幼体条件下黑点青鳉的生长特征和摄食行为发育。结果显示,幼体体长平均生长率为2.579%/d,体长与日龄间关系为y=3.132+0.383x-0.004x^2+0.00003x^3,R^2=0.98。通过各项摄食行为指标将其幼体生长发育分为3期6个阶段:仔鱼期(0~10 d)分为前仔鱼期(0~4 d)和后仔鱼期(5~10 d),稚鱼期(11~30 d)分为前稚鱼期(11~18 d)、中稚鱼期(19~24 d)和后稚鱼期(25~30 d),幼鱼期(31~65 d)。黑点青鳉幼体出膜4 d后开始投喂初孵卤虫,至10 d所有鱼苗均能捕食。黑点青鳉仔鱼期幼体死亡率较高,但摄食能力稳步提升,至该期末,摄食成功率提升至45%~55%,摄食效率达0.5~0.6个/min;稚鱼期幼体的各项摄食指标均有大幅度提升,对饵料的响应时间不断缩短,摄食速率提高,响应距离也逐渐增长,摄食量增大,摄食成功率已提升至90%~95%;幼鱼期各项摄食指标已接近成鱼,摄食效率达9个/min以上,摄食功能已趋于完善。研究表明,黑点青鳉在仔鱼期对卤虫无节幼体的响应距离短、摄食速率低下,摄食成功率与摄食效率均处于较低水平,随着其自身的发育以及摄食能力的稳定提升,摄食成功率和摄食效率逐步提高,成活率趋于稳定。养殖期间,通过密切注意黑点青鳉的摄食行为变化,改变投喂的数量和频次,使更多的仔鱼尽快过渡到稚鱼期,可能是提高养殖成活率的一条有效途径。     

Free amino acid and protein content in the planktonic copepod Temora longicornis compared to Artemia franciscana

Previous studies have indicated that natural zooplankton, the natural prey organisms of marine fish larvae, is superior to enriched Artemia spp. nauplii in supporting survival, growth and normal development of pigmentation and eye migration in Atlantic halibut larvae. The present study was designed to compare the amino acid dynamics in copepods harvested from a natural lagoon with that of enriched Artemia franciscana nauplii. The natural zooplankton in the present study was dominated by Temora longicornis, but varied in its developmental stage composition, apparent nutritional quality, amount and availability. The protein content in natural zooplankton varied from 31% to 54% of dry mass (DM) compared to 31% in enriched Artemia nauplii. The amount of free amino acids (FAA) in relation to protein was 14% in enriched Artemia nauplii and varied between 16% and 27% in zooplankton in two consecutive seasons. The FAA composition of zooplankton in 1996 was unaffected by stage and season, and showed a species-specific pattern. In response to starvation, two patterns in the amino acid dynamics of copepods were found. The first, exhibited by the major nonessential amino acids (NEAA), showed a continuous reduction in individual amount, while the second pattern, exhibited by the minor nonessential amino acids and all the essential FAA, had an initial increase followed by a reduction. It is suggested that the protein amount in DHA Selco™ (INVE)-enriched Artemia nauplii is too low in order to maximise the growth potential of some marine fish larvae as cod and halibut.     

A technical solution to the mass-culturing of larval turbot

A 1000 litre recirculation system of eight cylindrical rearing tanks has been tested in three 40-day periods to determine its capacity for rearing larval turbot (Scophthalmus maximus L.).The larvae were fed on rotifers and Artemia nauplii, as well as mixed marine algae. Continuous artificial light of 1500–2000 lux was applied at the surface. The applied algae served a dual function; keeping rotifers and Artemia at a high nutritional level as well as effectively removing the released ammonia. The combination of upwelling water and light at the surface maximized the contact surface between larvae, food items and algae.With this system, using a stocking density of 16 larvae litre^?1 in the rearing tanks, a survival total of 40% at Day 40 was achieved, giving a production of 6·4 larvae litre^?1 or 3000 larvae metre^?2 of the surface of the rearing tanks.     

Evaluation of frozen Umbrella‐stage Artemia as first animal live food for Litopenaeus vannamei (Boone) larvae

An alternative larval shrimp feeding regime, in which umbrella‐stage Artemia were constituting the first zooplankton source was evaluated in the culture of Litopenaeus vannamei. In a preliminary experiment, umbrella‐stage Artemia were fed to larvae from zoea 2 (Z2) to mysis 2 (M2) stages to identify the larval stage at which raptorial feeding starts and to determine daily feeding rates. The following experiment evaluated the performance of two feeding regimen that differed during the late zoea/early mysis stages: a control treatment with frozen Artemia nauplii (FAN), and a treatment with frozen umbrella‐stage Artemia (FUA). The ingestion rate of umbrella‐stage Artemia increased from nine umbrella per larvae day^?1 at Z2 stage to 21 umbrella per larvae day^?1 at M2. A steep increase in ingestion and dry weight from Z3 to M2 suggests a shift to a raptorial feeding mode at the M1 stage. Treatment FUA exhibited a significantly higher larval stage index (P < 0.05) during the period that zoea larvae metamorphosed to the mysis stage, and a higher final biomass, compared with treatment FAN. Based on these results and on practical considerations, a feeding regime starting with umbrella‐stage Artemia from Z2 sub‐stage can be recommended for L. vannamei larvae rearing.     

Optimisation of Artemia feeding rate for carp larvae (Cyprinus carpio L.)

Carp (Cyprinus carpio) larvae were fed on measured numbers of Artemia nauplii, and daily growth of the larvae monitored for a period of 10 days in order to determine the effect of varying feeding levels. A 34% reduction in specific growth rate was observed over the experimental period. At a temperature of 24 ± 0.5° C, carp larvae were found to require 200–250% of their body weight of Artemia nauplii per day for optimal growth and food conversion during the first five days of feeding, reducing to 100–120%/day over the following five days. The significance of these results is discussed in relation to potential economies of Artemia cyst use in hatcheries.     

Establishing larval feeding regimens for the Forktail Blenny Meiacanthus atrodorsalis (Günther, 1877): effects of Artemia strain,time of prey switch and co‐feeding period

This study aimed to establish feeding strategies covering the whole larval period of the forktail blenny, Meiacanthus atrodorsalis, based on the standard hatchery feeds of rotifers and Artemia. Three purposely designed experiments were conducted to determine the appropriate times and techniques to transition larvae from rotifers onto Artemia nauplii of a Great Salt Lake (GSL) strain, and a specialty AF strain, as well as subsequent transition onto enriched metanauplii of GSL Artemia. With a 3‐day co‐feeding period, larvae adapted well to a transition from rotifers to newly hatched GSL Artemia nauplii as early as 5 days posthatching (DPH), and as early as 3 DPH when fed the smaller AF Artemia nauplii. However, prolonging the rotifer‐feeding period up to 11 DPH did not negatively affect survival. Larvae fed Artemia nauplii of the AF strain showed 17–21% higher survival, 24–33% greater standard length and body depth, and 91–200% greater dry weight, after 20 days relative to those fed nauplii of the GSL strain. Meanwhile, enriched Artemia metanauplii of the GSL strain were shown to be an acceptable alternative to AF Artemia nauplii for later larvae, producing similar survival and growth when introduced from 8 DPH. Based on our findings, we recommend feeding M. atrodorsalis larvae rotifers as a first food between 0 and 2 DPH, introducing AF Artemia nauplii from 3 DPH, followed by enriched GSL Artemia metanauplii from 8 DPH onward, with a 3‐day co‐feeding period between each prey change.     

Effect of Rearing Density and Feeding Regimes on Growth and Survival of African Catfish,Heterobranchus longifilis (Valenceinnes, 1840) Larvae in a Closed Recirculating Aquaculture System

Heterobranchus longifilis larvae were reared over a 35 d period to evaluate the effects of stocking densities and feeding regimes on growth and survival. In experiment 1, larvae (12.3?±?2.1 mg) were stocked into glass aquaria at densities of 1, 2, 5, 10, 15, 20, and 25 larvae L^?1. Larvae were fed on Artemia nauplii ad libitum. Significant variations in terms of growth performance and feed utilization occurred at all levels of density treatments. Specific growth rate (SGR), body weight gain (BWG), and feed efficiency (FE) of the larvae decreased significantly as density increased. However, survival rate increased with the increase of stocking density. In experiment 2, larvae (13.4?±?1.1 mg) stocked at a density of 15 larvae L^?1, in the same conditions as experiment 1, were fed on three different regimes: Artemia nauplii; 35%?protein beef brain; and 35%?protein commercial catfish feed (CN⁺). SGR, BWG, and coefficient of variation (CV) of larvae fed on Artemia nauplii were significantly higher than those fed on beef brain and CN⁺. The survival rate of larvae fed on beef brain was significantly higher (88.40?±?9.75%) than those of Artemia (69.21?±?6.69%) and CN⁺ (40.40?±?6.22%). The results of this study suggest that the optimum stocking density is 15 larvae L^?1 and the beef brain can be used as alternative feed to Artemia in rearing H. longifilis larvae.     

Feeding experiments on the larvae of the fiddler crab Uca pugilator (Brachyura,Ocypodidae), reared in the laboratory

Larvae of Uca pugilator (Bosc) were reared in the laboratory from hatching to the megalopa stage on three different diets: (1) newly hatched Artemia salina nauplii (diet A), (2) the rotifer Brachionus plicatilis (O.F. Müller) and a ciliate Euplotes sp. (diet RC), and (3) a combination of the above two diets (diet ARC). The survival rate of zoeae fed diet A (90.0%) and diet ARC (93.8%) was much higher than that of the larvae fed diet RC (22.5%). The duration of the zoeal stages was significantly shorter for the larvae fed diet ARC than for those fed diets A and RC. The survival rate of megalopa larvae (reared on diets A and ARC in the zoeal stages) was high (above 90%) for megalopa fed Artemia nauplii only, as well as for those fed a combination of Artemia nauplii and shrimp. No significant differences in duration of the megalopa stage were found between the latter diet groups.     

Productivity improvement of Lysmata seticaudata (Risso, 1816) larval rearing protocol through modelling

The Monaco shrimp Lysmata seticaudata (Risso, 1816) is a marine ornamental species whose ecology and biology, as well as its larval culture has previously been addressed. The objective of the study was to predict and improve productivity of this species rearing protocol through modelling. The models developed intend to help aquaculturists to maximize survival to postlarva, decrease larval duration and increase synchronism of metamorphosis and newly metamorphosed postlarvae size by manipulating temperature, diet, first feeding period and stocking density.The models developed allow us to conclude that the L. seticaudata rearing protocol productivity can be improved by raising larvae at a density of 40 larvae L^− 1 and fed newly hatched Artemia nauplii since hatching to zoea V, and with Algamac 2000™ enriched Artemia metanauplii from zoea V to metamorphosis to postlarvae.By providing more productive protocols to aquaculturists, destructive practices and wild collection may be reduced.     

Morphological characterization of larval stages and first juvenile of the freshwater prawn Cryphiops caementarius (Molina, 1782) (Decapoda: Palaemonidae) under laboratory conditions

Research has been in progress for several years on various aspects of the biology and ecology of the freshwater prawn Cryphiops caementarius, an inhabitant of rivers in northern Chile. The commercial value of this prawn fomented the accomplishment of studies on its reproduction and development with the aim of producing juveniles under controlled conditions, to be followed by growout to commercial size in managed culture systems. The present study describes larval culture of this species from eggs of gravid females obtained in the field, from the first developmental stage (Zoea I) through the first juvenile stage. The larvae were cultured at 25 °C in UV sterilized water at variable salinities based on the requirements of the developmental stages. Larvae were fed with Nannochloris, Isochrysis and Artemia nauplii as required. This report describes in detail the 18 larval stages of this prawn, as well as its first juvenile form.     

Suitability of the copepod, Acartia clausi as a live feed for Seabass larvae (Lates calcarifer Bloch): Compared to traditional live-food organisms with special emphasis on the nutritional value

Though artificial propagation of Asian seabass Lates calcarifer (Bloch) in captivity through induced breeding techniques is standardized under Indian conditions, larval and nursery rearing techniques including suitable nursery feeds have to be standardized to obtain better survival and growth. Feeding experiments in triplicate were conducted to evaluate the suitability of the marine copepod Acartia clausi as live prey for fourteen day-old seabass larvae (6.53 ± 0.06 mm; 8.58 ± 0.33 mg) and compared with the traditional live prey, rotifers and Artemia nauplii. While A. clausi and rotifers were mass produced using algae Isochrysis galbana, Chaetoceros affinis and Chlorella marina, Artemia nauplii were produced using cysts. Nutritional quality of cultured copepods was evaluated based on the proximate composition, amino acid and fatty acid composition, and compared with that of rotifers and Artemia nauplii. Proximate composition varied significantly (P < 0.05) among the different live feeds. A. clausi showed higher protein (63.12%) and lipid (16.65%) content than Artemia nauplii and rotifers. Total essential amino acids content was 2% lower in A. clausi compared to that in Artemia nauplii. Fatty acid profiles of the live feed organisms showed that A. clausi is a rich source of n − 3 fatty acids. The total n − 3 fatty acid content of A. clausi was 33.94%. Length, weight overall weight gain and survivorship were significantly (P < 0.05) different among the dietary treatments, and weight gain was comparatively higher in A. clausi fed larvae. Survival of seabass larvae fed A. clausi was obtained highest as 58.13% against the lower values of 39.93% and 41.62% in larvae fed rotifer and Artemia nauplii respectively. Final carcass composition of the larvae of L. calcarifer fed different live-food organisms showed significant differences (P < 0.05) among the dietary treatments. The fatty acid composition of the dietary treatments was reflected to a certain extent in the fatty acid composition of the seabass larvae. The present investigation revealed the nutritional value of calanoid copepod and thus underlining its usefulness as a suitable live-food organism for rearing larvae of the commercially valuable Asian seabass.     

Early introduction of an inert diet and unenriched Artemia enhances growth and quality of Atlantic cod (Gadus morhua) larvae

The effects of two weaning diets and different weaning protocols on growth, survival, skeletal deformity and gut morphology of Atlantic cod larvae were studied in four groups from 16 to 45 days posthatch (dph). Cod larvae in groups 1 (early weaning with control diet) and 2 (early weaning with experimental diet) were used to evaluate the effects of different polar lipid content of weaning diets on larval and juvenile performance. Cod larvae in groups 2, 3 (early weaning with experimental diet + cofeeding with Artemia) and 4 (earlier weaning with experimental diet and earlier cofeeding with Artemia) were used to evaluate the effects of early introduction of dry diet and Artemia. From 45 to 170 dph, cod juveniles from all four groups were reared using a standard feeding protocol. No significant differences in growth, survival, deformities and gut morphology were found between cod larvae and juveniles from groups 1 and 2. Cod larvae fed on cofeeding regime with Artemia nauplii (groups 3 and 4) were bigger and had lower frequencies of jaw and neck deformities and higher foregut microvillus circumference than cod larvae from group 2. Our results demonstrate the importance of proper weaning protocols in producing better quality cod juveniles.     

The changes in the biochemical compositions and enzymatic activities of rotifer (<Emphasis Type="Italic">Brachionus plicatilis</Emphasis>, Müller) and <Emphasis Type="Italic">Artemia</Emphasis> during the enrichment and starvation periods

The changes in the biochemical compositions and enzymatic activities of rotifer (Brachionus plicatilis) and Artemia, enriched and stored at 4°C temperature, were determined. The total starvation period was 16 h and samples were taken at the end of the 8th and 16th hours. In present study, the rotifer and nauplii catabolized a large proportion of the protein during the enrichment period. Lipid contents of both live preys increased during the enrichment period and decreased in nauplii and metanauplii throughout the starvation period but lipid content of the rotifer remained relatively constant during the starvation period. The changes observed in the amino acid compositions of Artemia and the rotifer were statistically significant (P < 0.05). The conspicuous decline the essential amino acid (EAA) and nonessential amino acid (NEAA) content of the rotifer was observed during the enrichment period. However, the essential amino acid (EAA) and nonessential amino acid (NEAA) contents of Artemia nauplii increased during the enrichment period. The unenriched and enriched rotifers contained more monounsaturated fatty acid (MUFAs) than polyunsaturated fatty acid (PUFAs) and saturated fatty acids (SFA). However, Artemia contained more PUFAs than MUFAs and SFA during the experimental period. A sharp increase in the amounts of docosahexaenoic acid (DHA) during the enrichment of the rotifer and Artemia nauplii was observed. However, the amount of DHA throughout the starvation period decreased in Artemia metanauplii but not in Artemia nauplii. Significant differences in tryptic, leucine aminopeptidase N (LAP), and alkaline phosphatase (AP) enzyme activities of Artemia and rotifer were observed during the enrichment and starvation period (P < 0.05). The digestive enzymes derived from live food to fish larvae provided the highest contribution at the end of the enrichment period. In conclusion, the results of the study provide important contributions to determine the most suitable live food offering time for marine fish larvae. Rotifer should be offered to fish larvae at the end of the enrichment period, Artemia nauplii just after hatching and before being stored at 4°C, and Artemia metanauplii at the end of the enrichment and throughout the starvation period.