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1.
Larval growth, age, growth effect and instantaneous mortality were estimated in anchoveta, Engraulis ringens, collected biweekly during the austral winter of 2014 in nearshore waters off Bay of Antofagasta (23°41′W–70°30′S), northern Chile. Through measuring standard length (SL) and sagitta microstructure analysis, it was estimated that the growth rate of E. ringens larvae decreased from June (0.85 mm day?1) to August (0.50 mm day?1). However, the water temperature was homogeneous during the sampling dates (14.6, 15.2, 14.4, and 14.6°C), suggesting that the decelerating larval growth was not linked to changes in sea temperature. Additionally, larvae with slow growth have larger otoliths compared with conspecifics with fast growth (growth effect). Larval mortality rates tended to decrease until the middle of July (0.18 per day) but increased to 0.25 per day in early August, which coincided with lower food availability (i.e., chlorophyll‐a, 2.7–5.6 mg m?3) and a high occurrence of smaller larvae (1.58–11.5 mm). Partial least squares analysis indicates low covariance between the biological and oceanographic variables (PLS: 11.71%), suggesting that other factors, such as parental effects, may explain the abrupt decrease in the larval growth rates.  相似文献   

2.
A 16‐day experiment was designed to find the best combination of water temperature (27, 30, 33°C) and daily duration of food availability (12, 18, 24 h) for larval tench (Tinca tinca) growth and survival. Larvae with an initial mean size of 5.7 mm total length (TL) and 0.7 mg wet body weight (BW) were stocked at 15 L?1. Larvae were fed in excess with live Artemia nauplii with the period of food availability lasting 12, 18 or 24 h daily. The largest final larval size was recorded at 27 and 30°C in groups fed for 24 h a day (17.7 and 17.9 mm TL, 76.1 and 77.7 mg BW, respectively). The combination of the highest temperature and the longest daily food availability was the only set of conditions under which final larval survival was affected (95.4% survival; 98.7–99.9% under all other conditions). The combination of water temperature of about 28.6°C and continuous food availability is recommended as the optimum combination for rearing T. tinca larvae under controlled conditions. Providing continuous food supply to fish larvae under aquaculture conditions was also advantageous in helping to mitigate the effects of slower growth relative to developmental progress, which can occur at high water temperatures. However, should one wish to limit the daily feeding period to 12 h per day, the use of a water temperature between 27.4 and 27.9°C would be the best solution.  相似文献   

3.
Used as a traditional Chinese medicine, the high mortality rate and slow growth of Whitmania pigra larvae are the most serious bottlenecks for the scale development of artificial breeding. Firstly, five light colour treatments (white, blue, green, red and yellow) were tested to determine effects of light spectrum on the growth of larval W. pigra at the same intensity of 70.00 μmol m?2 s?1. The experiment lasted for 45 days. Under our experimental conditions, the weight gain (WG) and the specific growth rate (SGR) under blue light condition were significantly higher compared with the other treatments (P ≤ 0.05). It is reasonable to conclude that blue light can promote the leech growth. In addition, reared at five blue light intensity treatments (20.00 ± 3.84, 40.78 ± 4.18, 53.67 ± 5.98, 70.00 ± 7.26 and 87.33 ± 5.77 μmol m?2 s?1), the WG and SGR increased with increasing intensity. Meanwhile, they were significantly higher in the 70.00 and 87.33 μmol m?2 s?1 treatments (P ≤ 0.05). In the higher intensity light treatments, the digestive enzymes were higher and antioxidant enzymes were lower. These results suggest that the optimal light spectrum for the culture of W. pigra during the early life stage was blue and the optimal light intensity was higher light intensity (70.00–87.33 μmol m?2 s?1).  相似文献   

4.
The supply of microalgae to hatcheries is a limiting factor for the mass larval production of sea cucumber (Apostichopus japonicus) in Fujian Province, China. In this study, Nannochloropsis sp. isolated from the East China Sea was tested as food for A. japonicus larvae. The first trial compared the effect of mono‐, bi‐ and trialgal diets comprising three microalgae (Chaetoceros muelleri, Dunaliella tertiolecta and Nannochloropsis sp.) on A. japonicus larval growth, survival, settlement and juvenile growth. The results showed that there were no significant differences in survival and settlement between larvae fed with Nannochloropsis sp. and other diets. All diet treatments yielded similar juvenile sea cucumber output. In the second trial, A. japonicus larvae were fed equally four times daily at three different rations (5000, 20 000 and 40 000 cells mL?1 day?1). Larvae fed 20 000 cells mL?1 day?1 were significantly larger than larvae in other groups and experienced the highest survival rate. In the third trial, A. japonicus larvae were fed 20 000 cells mL?1 day?1 in three different frequency (2, 3 and 4 meals day?1). The greatest body length was observed in larvae that received 3 meals day?1. Survival and settlement of larvae fed 2 meals day?1 were significantly lower than other two groups. These results suggest that Nannochloropsis sp. can be used as a diet for the large‐scale production of A. japonicus seed, and larvae fed three times daily at a ration of 20 000 cell mL?1 day?1 are recommended for hatchery production of A. japonicus.  相似文献   

5.
Garlic, Allium sativum L., extract administered as a therapeutic bath was shown to have antiparasitic properties towards Neobenedenia sp. (MacCallum) (Platyhelminthes: Monogenea) infecting farmed barramundi, Lates calcarifer (Bloch). The effect of garlic extract (active component allicin) immersion on Neobenedenia sp. egg development, hatching success, oncomiracidia (larvae) longevity, infection success and juvenile Neobenedenia survival was examined and compared with freshwater and formalin immersion. Garlic extract was found to significantly impede hatching success (5% ± 5%) and oncomiracidia longevity (<2 h) at allicin concentrations of 15.2 μL L?1, while eggs in the seawater control had >95% hatching success and mean oncomiracidia longevity of 37 ± 3 h. At much lower allicin concentrations (0.76 and 1.52 μL L?1), garlic extract also significantly reduced Neobenedenia infection success of L. calcarifer to 25% ± 4% and 11% ± 4%, respectively, compared with 55% ± 7% in the seawater control. Juvenile Neobenedenia attached to host fish proved to be highly resistant to allicin with 96% surviving 1‐h immersion in 10 mL L?1 (15.2 μL L?1 allicin) of garlic extract. Allicin‐containing garlic extracts show potential for development as a therapy to manage monogenean infections in intensive aquaculture with the greatest impact at the egg and larval stages.  相似文献   

6.
Three in vivo experiments were conducted to measure the effectiveness of commercial Bacillus probiotics on survival and development of Litopenaeus vannamei larvae from nauplii 3–4 (N3–4) to zoea 3 (Z3) stages. Experiment I: Nine commercial Bacillus probiotics were individually added to larvae twice at N6 and Z1 at levels of 2, 20, and 100 mg L?1. Only six of nine products at 20 mg L?1 exhibited higher or significantly higher larval survival (P < 0.05) than the control. Experiment II: Two superior products from the first experiment were administered to larvae with six dose frequencies at 20 mg L?1. For both products, three doses, once at each of N3–4, N6 and Z1 stages, yielded the best larval survival and development rates (P < 0.05), and these were confirmed by enhanced activities of tryptase and amylase. Experiment III: The isolates of these two products, identified as Bacillus subtilis and Bacillus licheniformis, were delivered to larvae singly at concentrations of 1.0 × 108 and 1.0 × 109 CFU L?1, or at the same concentrations by mixing the two equally. At 1.0 × 109 CFU L?1, B. subtilis exerted more beneficial effects on larvae than B. licheniformis or the mixture. Therefore, the optimal dosage and dose frequency of commercial Bacillus products should be evaluated prior to large‐scale application in shrimp hatcheries to avoid futility or even adverse effects, as spore counts and non‐bacterial ingredients are key factors influencing the efficacy of Bacillus probiotics.  相似文献   

7.
In this study, we aimed to investigate the effects of water temperature and stocking density on the survival, feeding and growth of the juveniles of the hybrid yellow catfish from Pelteobagrus fulvidraco (♀) × Pelteobagrus vachelli (♂) using the parameters as follows: survival rate (%), feeding rate (% day?1), feed conversion ratio, specific growth rate (% day?1), coefficient of variation (%), productivity (P, g m?3 day?1) and condition factor. We reared the juvenile fish (3.25 ± 0.21 g) at 12 water temperature levels and six stocking density levels (each level included three aquaria in two batches of experiments). The results showed that all groups survived at a temperature range of ≤35°C during a 46‐day experimental period, and they could achieve a high growth at a water temperature range of 26–32°C. The optimal temperature for growth was 29.8°C. Productivity peaked at a stocking density of 1.9 kg m?3. Our results indicated that the hybrid is very suitable for commercial aquaculture.  相似文献   

8.
The effect of temperature (10, 13, 16, 19 and 22°C) on hatching, development and survival of yolk‐sac larvae of European hake, Merluccius merluccius, was studied. At 22°C the experiment was suspended because all eggs died a few hours after incubation. Five morphological indicators of larval development (standard length – SL, yolk‐sac volume – YSV, oil globule diameter – OD, body height – BH and body wet weight – BW) were analysed. SL, YSV, OD and BW of newly hatched larvae were biggest in size and weight at low temperatures (P < 0.05). Throughout the experiments, the rates of changes in SL, YSV and OD varied with temperature (P < 0.05). By contrast, BH and BW remained constant and did not show significant relationship with the effect of temperature (P > 0.05). The potential model showed that the SL growth rate varied from 0.05 to 0.08 mm day?1 from 10.5 to 19.5°C respectively. However, at all temperatures two growth phases were identified: a rapid growth phase followed by a slow one. Rapid growth rate in length and depletion in yolk‐sac and oil globule occurred at high temperatures. After total YSV and OD consumption (death by starvation), larvae died between 8 and 14 days at 19.5 and 10.5°C respectively, reaching a maximum length of 4.3 mm at 10.5°C. Metabolic indices such as: lowest threshold temperature (T0); effective larval development (); cumulative thermal units (TC) to complete larval development; the temperature coefficient on growth rate in length (Q10) and the condition factor (K) were also studied.  相似文献   

9.
Feed requirements were estimated from specific growth rates in standardized soft tissue dry weight (SGRDW’) and atomic O:N ratios for mussels fed seven rations of microalgae (5–735 μg C h?1 ind?1) at 7 and 14°C respectively. The mean oxygen consumption and ammonia‐N excretion rates were significantly higher at 14°C (0.29 μg O2 and 27.3 μg N ind?1 h1) compared with those at 7°C (0.16 μg O2 and 11.4 μg N ind?1 h?1) (P < 0.05), resulting in O:N ratios between 3 and 45 at 7°C and 7 and 28 at 14°C. Low O:N ratios indicate protein catabolism and an unfavourable condition, whereas high ratios indicate that carbohydrate is the primary energy source. The measured SGRDW’ suggests minimum feed requirements of ~240 and ~570 μg C ind?1 h?1 for weight maintenance at 7 and 14°C, with corresponding O:N ratios of 24 and 16, respectively, indicating a more stressed condition at 14°C. A 0.5% SGRDW’ day?1 was obtained by ~565 (O:N = 29) and ~680 (O:N = 23) μg C ind?1 h?1 at 7 and 14°C respectively. A positive and significantly higher SGRDW’, with the lowest feed ration at 7°C compared with a negative SGRDW’ at 14°C (P < 0.05), indicated that storage time can also possibly be prolonged at low temperatures if the mussels are not fed.  相似文献   

10.
The current study investigates whether it is possible to increase the meat content of captive male king crab (Paralithodes camtschaticus) (average = 2.2 kg) by feeding manufactured diets at different temperatures (4°C, 8°C and 12°C). A 110 days trial was undertaken with groups of male king crabs held in 12 land‐based holding tanks. All crabs survival in the lowest temperature treatment, one animal died in the medium‐temperature group (8°C) and four animals in the highest temperature treatment (12°C). The results showed that feed intake increased with increasing temperature from an average of 1.0 g kg?1 day?1 at 4°C to 2.8 g kg?1 day?1 crab at 12°C. The percentage meat content was significantly higher at the final census (60.0%) compared with the initial census (37.5%) in all temperature groups, but there were no significant differences in the percentage meat content of the king crabs held in the different temperature treatments at the conclusion of the experiment. Oxygen consumption was also significantly affected by temperature and increased with increasing temperature. The results of the experiment show that the optimal temperature to maintain, and enhance, the meat content of king crab is close to 4°C.  相似文献   

11.
Live prey used for marine larval fish (rotifers and Artemia) as well as intensive larval rearing conditions are susceptible to the proliferation of bacteria that are the cause for reduced growth and larval mortality. Hydrogen peroxide has been recently proved a good disinfectant in aquaculture, either for eggs, larvae or live prey. In this study the effects of a hydrogen peroxide‐based product, Ox‐Aquaculture©, on live prey (rotifers and Artemia) and meagre larvae bacterial load, composition and final status have been tested. A 34.6% reduction of total heterotrophic bacteria and 59.7% of Vibrionaceae were obtained when rotifers were exposed for 15 min to 40 mg L?1 of the product. A 34.3% reduction of total heterotrophic bacteria and 37.7% of Vibrionaceae were obtained when Artemia were exposed for 5 min to 8000 mg L?1 of the product. More than 95% reduction of total heterotrophic bacteria and 75% of Vibrionaceae were obtained when meagre larvae were exposed for 1 h to 20 mg L?1 of the product. Furthermore, disinfection of enriched live prey with the product did not change the fatty acid composition and survival of the live prey and improved final larval survival.  相似文献   

12.
Piaractus mesopotamicus juveniles (total length 12 ± 0.5 mm) were exposed to different concentrations of ammonia‐N (un‐ionized plus ionized ammonia as nitrogen), using the static renewal method at different temperature levels (15, 20 and 25°C) at pH 7. The 24, 48, 72, 96 h LC50 values of ammonia‐N in P. mesopotamicus juveniles were 5.32, 4.19, 3.79 and 2.85 mg L?1 at 15°C; 4.81, 3.97, 3.25 and 2.50 mg L?1 at 20°C; and 4.16, 3.79, 2.58 and 1.97 mg L?1 at 25°C respectively. The 24, 48, 72, 96 h LC50 values of NH3‐N (un‐ionized ammonia as nitrogen) were 0.018, 0.014, 0.013, 0.009 mg L?1 at 15°C temperature; 0.023, 0.019, 0.016 and 0.012 mg L?1 at 20°C; 0.029, 0.026, 0.018 and 0.014 mg L?1 at 25°C. The temperature increase from 15 to 25°C caused an increase of ammonia‐N susceptibility by 21.80%, 9.55%, 31.92% and 30.87%, after 24, 48, 72 and 96 h exposure respectively. Furthermore, we found that exposure of fish to ammonia‐N caused an elevation in total haemoglobin and blood glucose with an increase of 2 mg L?1 concentration. Ammonia levels tolerated, especially in different temperatures levels, have important implications for the management of aquaculture.  相似文献   

13.
Harvesting practices of the clam Chionista fluctifraga show a decline in commercial size and densities, but no strategies have been developed to maintain clam beds. Aquaculture represents an alternative for preserving this resource. Adult clams from commercial grounds were used as broodstock. Conditioning, induction of spawning, cultivation of larvae, settlement of eyed larvae and nursing of postlarvae were performed in the hatchery for producing spat. Larvae and postlarvae were used to measure increase in shell height and data were fitted to exponential growth models. Spat were placed in floating trays and maintained in off‐bottom cultivation for 9 months. Samples of clams and tissues were collected monthly to measure absolute growth, shell height increase and a condition index. Larvae, postlarvae and juveniles showed exponential growth patterns. Mean shell height increased about 0.030 mm day?1 during larval and post‐larval stages and 0.049 mm day?1 during field cultivation. Pediveligers (height 215 ± 83 μm) entered metamorphosis at days 9–13 after fertilization, and postlarvae reached 3011.7 ± 325.5 μm (height) at day 60. After field cultivation, survival was about 95%; juvenile shell height was 20.6 ± 2.2 mm, and total weight was 5.3 ± 0.7 g. Growth rates were superior to natural conditions and the condition index was high throughout the study. Our results show that spat of C. fluctifraga can be produced in the hatchery, and that field production can be maintained in off‐bottom trays until reaching commercial size. Aquaculture activities for this species need to be established and evaluated.  相似文献   

14.
The present study evaluated various sodium and potassium concentrations in hatchery water to determine which proportions would be optimal for Macrobrachium rosenbergii larviculture. Using a closed RAS system (60‐L), experiments were conducted in two stages. In the first stage, larval quality parameters were compared among triplicate treatments of sodium (2000, 3000, 4000 and 5000 mg L?1) and potassium (100, 150, 200 and 250 mg L?1). During the second stage, these same parameters were compared from interactions of the two best concentrations determined in the first stage. Initial larval density was fixed at 100 larvae L?1 and larval quality parameters such as larval stage index (LSI), larval condition index (LCI), larvae dry weight, survival (%), LC50‐24 h for formalin stress and time of the first postlarvae (PL) appearance were measured. Results showed that during the early larval period time LSI, LCI and survival parameters were affected only by potassium and the interaction with sodium was not significant. At a later period of the larval development, interactions between both sodium and potassium were measurable for LSI (P < 0.05) while the interactions on LCI and survival were not significant. Measurable differences among the combined treatments 4000 mg L?1 sodium and 150 mg L?1 potassium resulted in the best performance for M. rosenbergii larviculture. This concentration also provided the highest final survival to PL metamorphosis (40.6 ± 2.5%) which was at least 10% higher than the other treatments.  相似文献   

15.
Feeding copepods during early larval culture stages of marine fish has proven to be advantageous for growth and survival of marine finfish larvae. However, commercial availability of most copepods is limited; thus, there is an impetus to evaluate promising copepod species to meet the diverse dietary demands of various marine fish. The marine cyclopoid copepod, Oithona colcarva, was isolated out of zooplankton samples taken from waters within Tampa Bay, Florida. Once isolated, trials were conducted to determine the appropriate culture parameters for producing nauplii to feed marine fish larvae. The effects of temperature (22°C, 26°C and 30°C), salinity (15, 20, 25, 30 and 35 g L?1), stocking density (0.5, 1.0, 2.0, 4.0 and 8.0 individuals mL?1) and diet (Nanno 3600 microalgae paste, Colurella adriatica, Rhodomonas lens, Tisochrysis lutea, Chaetoceros gracilis and/or Tetraselmis chuii) on nauplii production during a single life cycle of reproducing individuals were examined. Results of those trials indicated that a culture temperature of 30°C and a salinity of 30 g L?1 were advantageous for maximum nauplii production. Furthermore, a diet containing a 1:1:1 mixture of T. lutea, C. gracilis and T. chuii and a stocking density of at least 8 individuals mL?1 were identified as beneficial. The results of these trials, the potential for large‐scale culture and observations on the performance of marine fish larvae fed Oithona colcarva nauplii are discussed.  相似文献   

16.
Argyrosomus regius (3.0 ± 0.9 g) were exposed to different concentrations of ammonia in a series of acute toxicity tests by the static renewal method at three temperature levels (18, 22 and 26°C) at a pH of 8.2. Low temperature clearly increased the tolerance of the fish to total ammonia nitrogen (TAN) and unionized ammonia (NH3) (P < 0.05). While the 96‐h LC50 values of TAN were 19.79, 10.39 and 5.06 mg L?1, the 96‐h LC50 of NH3 were 1.00, 0.70 and 0.44 mg L?1 at 18, 22 and 26°C respectively. The safe levels of NH3 for A. regius was estimated to be 0.10, 0.07 and 0.04 mg L?1 at 18, 22 and 26°C respectively (P < 0.05). This study clearly indicates that A. regius is more sensitive to ammonia than other marine fish species cultured on the Mediterranean and Eastern Atlantic coasts.  相似文献   

17.
Salinity tolerance and growth of Japanese flounder Paralichthys olivaceus at different developmental stages were evaluated, including newly hatched larvae (nhl), yolk sac larvae (ysl), oil droplet larvae (odl), post oil droplet larvae (podl), premetamorphic larvae (preml) and prometamorphic larvae (proml), at 11 salinities from 5 to 55 g L?1 for 96 h. The ontogenesis during the early life of P. olivaceus was investigated under hatchery salinity 35 g L?1. The results showed that suitable salinities for nhl, ysl, odl, podl, preml and proml larvae were 10 to 25 g L?1, 10 to 30 g L?1, 20 to 30 g L?1, 30 g L?1, 10 to 30 g L?1, 15 g L?1, respectively, demonstrating an ontogenetic variation of salinity tolerance. The salinity tolerance of nhl, ysl, preml was higher than that of odl, podl and proml. The ysl and preml larvae displayed wide salinity tolerances. The present findings demonstrate that the suitable salinity for larviculture of P. olivaceus is 20–25 g L?1 before the depletion of oil droplet; after that, higher salinity (30 g L?1) should be ensured for the post‐oil droplet larvae; the premetamorphic larvae can be cultured at a wide salinity range (10–30 g L?1), and the metamorphosed larvae should be reared at salinity about 15 g L?1.  相似文献   

18.
The digestible protein (DP) and digestible energy (DE) requirements for maintenance and growth of brook trout (Salvelinus fontinalis) were determined using a factorial model at either optimum (15 °C) or elevated temperature (19 °C). Several key parameters of the factorial model were measured using a series of inter‐related studies. The maintenance requirements for DP and DE were 0.10 gDP kg?0.69 day?1 (15 °C) and 0.31 gDP kg?0.78 day?1 (19 °C), and 34.86 kJDE kg?0.84 day?1 (15 °C) and 46.14 kJDE kg?0.86 day?1 (19 °C). The total requirements for DP were 0.10 gDP kg?0.69 day?1 + 2.14PG (protein gain) (15 °C) and 0.31 gDP kg?0.78 day?1 + 1.98PG (19 °C). The total requirements for DE were 36.86 kJDE kg?0.84 day?1 + 1.58EG (energy gain) (15 °C) and 46.14 kJDE kg?0.86 day?1 + 1.64EG (19 °C). The partial efficiencies for growth were 0.47 (15 °C) and 0.51 (19 °C) for protein, and 0.63 (15 °C) and 0.61 (19 °C) for energy. Nutrient gain was lower at the elevated temperature; however, feed formulation for brook trout should be adjusted to match changes in nutrient requirements at different culture temperatures. The protein and energy requirements model will be useful for developing commercial feeds and feeding charts for brook trout.  相似文献   

19.
During April to June 2009, a large bolus of Amazon River water impacted the northeastern Caribbean Sea. Shipboard observations collected near Saba Bank, the U.S. and British Virgin Islands, and the Anegada Passage showed low surface salinity (35.76 ± 0.05 Practical Salinity Unit (PSU)), elevated surface temperature (26.77 ± 0.14°C), high chlorophyll‐a (1.26 ± 0.21 mg m?3) and high dissolved oxygen (4.90 ± 0.06 mL L?1) in a 20‐ to 30‐m thick surface layer in the riverine plume. The water was ~1°C warmer, 1 PSU fresher, 0.3 mL L?1 higher in oxygen and 1.2 mg m?3 higher in chlorophyll‐a than Atlantic Ocean waters to the north, with Caribbean surface waters showing intermediate values. Plankton net tows obtained in the upper 100 m of the water column revealed larval fish assemblages within the plume that were significantly different from those of the surrounding waters and from those encountered in the area in previous years. The plume waters contained higher concentrations of mesopelagic fish larvae from the families Myctophidae and Nomeidae, which as adults typically inhabit offshore, deep water habitats. Concentrations of larvae from inshore and reef‐associated families such as Scaridae, Serranidae, Labridae and Clupeidae were lower than those found outside the plume in similar shallow areas, particularly in near‐surface waters. An event like the one observed in 2009 had not been documented in at least the past 30 yr, and yet it was followed by another similarly extreme event in 2010. The ecological implications, including any long‐term consequences of such recent extreme events, are important and merit further study.  相似文献   

20.
In order to optimize Pecten maximus larval performance and post-larval yield, larvae were fed five algal concentrations in the range 3–20 cells μL?1 in 2,800-L flow-through tanks without prophylactic antibiotics. Competent larvae were transferred to a commercial hatchery for settlement and provided uniform conditions for 4 weeks to observe effects. Increased diet concentration increased the sum of fatty acids (FA) in the total larval population, reaching 7 and 25 ng FA larvae?1 at 3 and 16 cells μL?1, respectively. The FA level in competent larvae was not affected by diet concentration and ranged from 30 to 46 ng larvae?1. Increased diet concentration increased larval growth rate, and the larvae were ready to settle 5 days earlier when fed 16 cells μL?1 compared to 3 cells μL?1. Larval ingestion rate increased during life span and with increased larval diet concentrations, but a considerable amount (40–60 %) of the added algal cells was lost from the larval rearing tanks due to the seawater flow. There was no effect on larval survival, final post-larval shell height, % of competent larvae transferred to settlement, or total yield of post-larvae. Final mean post-larval shell height was 509 μm and 25.5 % of competent larvae settled, resulting in a final post-larval yield between 6.9 and 17.6 % of the initial number of d3 larvae. Competent larvae with similar FA content produced similar numbers of post-larvae independent of diet concentration, even if higher diet concentrations resulted in higher rates of larval development and metamorphosis.  相似文献   

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