Effects of mono‐species and bi‐species microalgal diets on the growth,survival and metamorphosis of auricularia larvae of the California sea cucumber,Parastichopus californicus (Stimpson, 1857)

The effects of mono‐species and bi‐species microalgal diets on body length, survival and metamorphosis of auricularia larvae of the California sea cucumber, Parastichopus californicus, were tested in two separate laboratory feeding experiments. The first examined eight single species of microalgae – Chaetoceros calcitrans (Cc), Chaetoceros muelleri (Cm), Dunaliella tertiolecta (Dt), Isochrysis sp. (Tahitian strain: TISO) (Ti), Pavlova lutheri (Pl), Phaeodactylum tricornutum (Pt), Tetraselmis suecica (Ts) and Thallassiosira pseudonana (Tp). The second experiment took the five most effective single species from the first experiment (i.e. Cc, Cm, Dt, Pl and Ti) and presented them in all possible binary combinations. In the first experiment, Cc was determined to be the best diet on the basis of generating a significantly higher metamorphic rate (65.5 ± 4.2%, mean ± SD) than any other species and leading to one of the best survival rates (72.3 ± 7.6%) and greatest body lengths (831.6 ± 5.6 μm at day 14). In the second experiment, diets containing Cc generally produced the highest survival and metamorphic rates and greatest body lengths (except Cc/Cm) of all mixed diets, although no bi‐species treatment was ever significantly superior to a control of Cc alone. Of the various mono‐species and bi‐species diets evaluated for rearing auricularia larvae of P. californicus, Cc (either alone or mixed with other species) is recommended.     

Effect of different dietary microalgae combinations on growth and survival of black‐lip pearl oyster (Pinctada margaritifera) larvae and the feasibility of replacing microalgae with a dietary lipid emulsion

A 10‐day experiment was performed to examine different mono, binary and ternary dietary combinations on survival and growth of D‐shaped and umbone black‐lip pearl oyster, Pinctada margaritifera, larvae. The three tropical microalgae species were the flagellate Isochrysis galbana clone T. Iso (CS‐177) and diatoms Chaetoceros calcitrans (CS‐178) and Chaetoceros muelleri (CS‐176) which were fed to D‐shaped and umbone larvae at a density of 7000 and 14 000 cells mL^?1, respectively. A second experiment was performed to investigate the feasibility of replacing T. Iso with a lipid emulsion for both D‐shaped and umbone larvae for 10 and 12 days, respectively. The treatments included only T. Iso, unfed and lipid emulsion to substitute T. Iso at levels of 10% (LIP10), 30% (LIP30) and 100% (LIP100). In the first experiment, results showed that a monospecific diet of T. Iso led to significantly higher (P < 0.05) survival and growth of D‐shaped larvae than all the other treatments. Meanwhile, D‐shaped larval survival was significantly lower when only fed C. calcitrans as well as growth for those fed C. calcitrans or in combination with C. muelleri. However, for umbone larvae, survival and growth were significantly higher when fed a binary combination of T. Iso and C. muelleri or the ternary combination of T. Iso, C. muelleri and C. calcitrans compared with all other treatments. For the second experiment, results showed that with increasing lipid emulsion replacement, survival of both D‐shaped and umbone larvae significantly decreased (P < 0.05); however, the LIP100 treatment was not significantly different (P > 0.05) from the unfed treatment. For D‐shaped larvae, no significant growth difference was detected (P > 0.05) between the T. Iso and LIP10 fed treatments while for umbone larvae, the T. Iso, LIP10 and LIP30 were not significantly different (P > 005). These results indicate that microalgae combinations appear more necessary for later staged P. margaritifera larvae. In addition, the use of a lipid emulsion appeared to provide some nutrition to the larvae, although more research should be conducted to improve the use of such replacements.     

Influence of different microalgal diets on gonadal development of the carpet shell clam <Emphasis Type="Italic">Ruditapes decussatus</Emphasis> broodstock

Studies considering broodstock conditioning of Ruditapes decussatus mostly used flagellates and diatoms for feeding, mainly Isochrysis galbana and Chaetoceros calcitrans, respectively. The present study evaluated the effect of different microalgal diets on gonadic maturation of R. decussatus including three microalgae species (C. calcitrans, Tetraselmis suecica, and Nannochloropsis oculata) which were used to prepare six diets: three monospecific and three bispecific mixed diets at a proportion of 1:1. Clams were daily fed at a ratio of 1% dry weight of algae/live weight of clam and unfed treatment was used as control. Results showed that clams fed C. calcitrans alone or mixed with T. suecica attained earlier full maturity with the highest response to spawning induction (after 34 conditioning days) and largest proportion in the partial spawning phase for both, followed by T. suecica alone after 48 days. In contrast, N. oculata alone or mixed diets demonstrated poor performance for gonadal maturation. Unfed treatment did not show any sign of maturation. The results indicated that T. suecica has high conditioning potential like C. calcitrans and their mixture gave the highest benefit. Therefore, T. suecica can be recommended for R. decussatus broodstock conditioning.     

Growth and Survival of Larval Sandfish,Holothuria scabra (Echinodermata: Holothuroidea), Fed Different Microalgae

This study assessed the nutritional value of four species of microalgae for larval sandfish, Holothuria scabra (Echinodermata: Holothuroidea). Two‐day‐old larvae were fed either a single diatom (Chaetoceros muelleri, Chaetoceros calcitrans), flagellate (Isochrysis aff. galbana (T‐ISO), Pavlova salina), or a ternary microalgal diet (TMD) comprised of 40% C. muelleri, 40% T‐ISO, and 20% P. salina for 12 d. On Days 4, 6, and 8 length of larvae fed either C. muelleri, C. calcitrans, or the TMD was significantly greater than in T‐ISO and P. salina fed larvae as well as the unfed control larvae. T‐ISO fed larvae had a significantly greater length compared to unfed larvae on Days 4, 6, and 8; however, larvae fed P. salina had a significantly greater length compared to unfed larvae on Days 6 and 8 only. Survival of larvae fed either C. muelleri or the TMD was significantly better than the flagellate fed and unfed larvae on Days 4, 8, and 12. There was no significant difference between survival of unfed larvae and larvae fed either T‐ISO or P. salina during the 12‐d larval culture period. On Day 12, larvae fed either a diatom or the TMD developed in excess of 84% competent doliolariae. Larvae fed C. muelleri had a significantly higher percentage competent doliolariae than larvae from all other treatments except the TMD. Neither larvae fed either T‐ISO or P. salina nor unfed larvae developed any competent doliolariae. In conclusion, this study showed C. muelleri to be the most effective of the four microalgae tested as a single microalgal diet for larval H. scabra and, as such, C. muelleri will be used as a reference diet in future studies.     

Effects of selected mixed‐algal diets on growth and survival of early postset juveniles of the Pacific geoduck clam,Panopea generosa (Gould, 1850)

Four microalgal species [Dunaliella tertiolecta, Phaeodactylum tricornutum, Tetraselmis suecica, Thalassiosira pseudonana], previously identified as poor single‐algal diets for juvenile geoduck clams, Panopea generosa, were selected to mix with two comparatively better food‐value microalgae [Isochrysis sp. (TISO), Chaetoceros muelleri (CM)] to estimate synergistic or non‐additive effects of mixed microalgae on the growth/survival of young juveniles of P. generosa. In addition, the effects of different TISO/CM proportions [75/25, 50/50, 25/75; ash‐free dry weight (AFDW) basis] on growth/survival were assessed. Shell length, wet weight, dry weight, AFDW and organic matter content were significantly increased when using mixed TISO diets compared with TISO alone. In contrast, there were no significant differences with these variables when comparing mixed CM diets with CM alone. Ultimately, the best diet in terms of length and weight enhancement was a previously identified optimal one of TISO/CM (50/50). Survival on day 23 (60.7–79.3%) was not significantly different among any of the 11 diets tested. There were no significant differences in shell length, wet weight, dry weight, AFDW and organic matter content among the three TISO/CM ratios tested, but these diets gave superior results to TISO and CM fed alone. Survival (60.7–74.7%) on day 23 in the three TISO/CM ratios tested did not vary significantly.     

Culture of the calanoid copepod Pseudodiaptomus euryhalinus (Johnson 1939) with different microalgal diets

The copepod Pseudodiaptomus euryhalinus was fed 320 cells μL^− 1 of monoalgal cultures of Chaetoceros muelleri, Nannochloropsis oculata, Isochrysis galbana, Tetraselmis suecica, or a commercial frozen concentrate of Tetraselmis sp., and the diet which gave the best production was compared in a second experiment to three mixed diets: C. muelleri:I. galbana supplied in 1:1 and 2:1 cell ratios and C. muelleri:I. galbana:frozen Tetraselmis sp. in 2:2:1 ratio. These gave better results than the cultures of N. oculata, I. galbana, T. suecica and the frozen Tetraselmis concentrate, but the production was similar to that obtained with C. muelleri supplied as a monoalgal diet, showing that the addition of C. muelleri may improve the performance of other monoalgal diets, whereas the addition of other microalgae is unlikely to improve the results obtained when C. muelleri is supplied as a monoalgal diet.     

Gonadic conditioning and maturation of the queen conch (Dosinia ponderosa) fed three microalgae at three temperatures

Gonadic conditioning and maturation of queen clam Dosinia ponderosa fed three microalgae (Isochrysis galbana, Tetraselmis suecica and Chaetoceros calcitrans) at three temperatures (20, 25 and 30°C) were assessed. Histological analysis showed six gonadic stages, indicators of maturity. The evaluation included sex proportion, oocyte diameter and frequency of gonadic stages after 22 (middle of trial) and 44 days (end of trial). At day 22, around 60% of females conditioned at 20°C, reached stage III (advances grade of maturation) when fed T. suecica. At day 44, around 50% of females were on stage III, conditioned at 20 and 25°C and fed T. suecica and C. calcitrans. For males, the best combination was C. calcitrans at 20 and 25°C. The temperature of 30°C resulted inadequate for maturation, especially when fed the diatom Isochrysis galbana. High mortalities occurred at that temperature with the three microalgal diets, especially in females. The results permits conclude that T. suecica and C. calcitrans are good sources of feed for D. ponderosa and that the best range of temperature for gonadic development is 22–25°C. These results may be basic for a best management and culture of this clam.     

Evaluation of the Microalgae Paste Viability Produced in a Mollusk Hatchery in Southern Brazil

The present study was conducted to define a methodology to produce and store small‐scale microalgae paste to be used in a mollusk hatchery. Microalgae were cultured in 500 L fiberglass tanks, under temperature of 20 ± 2 C, Guillard f/2 culture medium, and continuous light intensity of 203–226 μmol photons/m²/sec. Cultures were centrifuged at 2000 g at the exponential growth phase. Microalgae cell quality after centrifugation and during storage was determined by analyses with Evan’s blue stain and by counting the number of total marine bacteria. Treatments with and without additive were applied to the microalgae paste produced, which was distributed into 100 mL plastic containers, capped, and stored under refrigeration at 4 ± 1 C. Results indicated that in the Chaetoceros muelleri paste, centrifugation did not damage the cells and the number of total marine bacteria reduced significantly from 2.9 × 10⁶ to 8.3 × 10⁵ colony‐forming units per milliliter. Chaetoceros muelleri and Chaetoceros calcitrans pastes stored with addition of 0.1% ascorbic acid had a shelf life shorter than 2 wk. For the treatment without additive, results with Evan’s blue stain showed that cells (99%) remained viable until the sixth week of storage for C. muelleri and seventh week of storage for Skeletonema sp. and C. calcitrans. The number of bacteria did not increase during storage for C. calcitrans and Skeletonema (P > 0.05). For C. muelleri, an increase in bacteria (P < 0.05) was observed after the sixth week of storage. This study demonstrated the feasibility to produce and store microalgae paste for a period of 2–8 wk, which allows it to be used as food source and also optimizes the use of microalgae cultured in laboratory.     

Diet trials on tehuelche scallop Aequipecten tehuelchus (d''Orb) larvae

Laboratory spawned one week old veliger larvaeof the tehuelche scallop, Aequipectentehuelchus (D'Orb., 1846), were reared topedivelger stage under three different dietaryregimes in order to determine the best algalcombination under standard hatchery conditions.Veligers were cultured at mean densities of 2.7larvae/ml. Larval growth and survival wereassessed on larvae fed the following dietarytreatments: (1) Isochrysis galbana(T-Iso)+ Chaetoceros calcitrans, (2)Pavlova lutheri + C calcitrans, and (3)P. lutheri + I. galbana T-Iso +Ch. calcitrans. The highest growth rateswere detected on larvae fed diets includingP. lutheri.     

Digestion of lipids and carbohydrates from microalgae (Chaetoceros muelleri Lemmermann and Isochrysis aff. galbana clone T‐ISO) in juvenile scallops (Pecten maximus L.)

The digestion of laminaran and neutral lipids from the microalgae Chaetoceros muelleri or mixtures of C. muelleri and Isochrysis galbana clone T‐ISO in 4‐mm scallops Pecten maximus were studied. The microalgae were cultivated at fixed low and high growth rate (5% and 60% of μ_max). The cultivation method clearly affected the lipid and carbohydrate contents, as well as their enzyme activity. Chaetoceros muelleri and T‐ISO grown at low growth rate exhibited a considerably higher content of lipids and carbohydrates than those algae grown at high growth rate. The specific activity of laminaranase and neutral lipase was the highest in C. muelleri grown at the low growth rate. Growth rate of scallops was best when they were fed a mono‐species diet of C. muelleri grown at low growth rate. The growth rate of the scallops was positively correlated to the dietary carbohydrate content as well as to the specific activity of neutral lipase and laminaranase in the diet. The capacity to digest carbohydrates (laminaran) might be limiting for the young scallops, and the content of carbohydrates and enzymatic activities of laminaran in the diet should be considered when formulating an optimal diet, both when the diet consist of live microalgae and formulated diets.     

Improving the fitness of Holothuria arguinensis larvae through different microalgae diets

Development and design of adequate feeding protocols on sea cucumber larvae are necessary for improvements on larvae growth, survival and production of competent juveniles. This work assessed the Holothuria arguinensis larvae growth and survival, fed with three different single microalgae diets of Chaetoceros calcitrans, Isochrysis galbana and Tetraselmis chui, and two microalgae diets based on a combination of C. calcitrans and T. chuii (C:T; 1:1) and C. calcitrans, T. chuii and I. galbana (C:T:I; 1:1:1) during 2 months. Holothuria arguinensis larvae fed with T:C:I, showed higher survival and larger larval and stomach sizes than the ones fed with the other diets. Comparing the results obtained from the single diets, H. arguinensis larvae fed with I. galbana grew and survived better during the first 5 days. However, higher growth was obtained on the larvae fed with C. calcitrans from day 5 to day 12; since this day, larvae fed with T. chuii showed the largest size. These results could be related to the different microalgae size and morphology, in addition to the nutritional value of the different microalgae used. However, no competent larvae that metamorphosed into doliolaria were obtained during this experiment. The tanks used were transparent, which could be causing light stress to the larvae, since competent larvae were obtained in opaque production tanks in our aquaculture installations during the same time period. The combined diet of C. calcitrans, T. chuii and I. galbana (C:T:I) could improve the growth and larvae competency of H. arguinensis.     

Broodstock conditioning of the Portuguese oyster (Crassostrea angulata,Lamarck, 1819): influence of different diets

The Portuguese oyster Crassostrea angulata shows great potential in oyster farming. The conservation of pure populations of this species is important for production diversification and biodiversity preservation. In this way, the zootechnological development for seed hatchery production is extremely important. Broodstock conditioning is a key step in the process of rearing bivalves in a hatchery. Many factors regulate the reproductive cycle, being food one of the most important ones. To evaluate the effect of different diets on C. angulata reproductive performance, broodstock were conditioned with different food regimes formulated fundamentally by flagellates (Diet 1 – Pavlova lutheri and Isochrysis galbana clone T‐ISO; Diet 2 – P. lutheri, T‐ISO and Skeletonema costatum) and constituted fundamentally by diatoms (Diet 3 – S. costatum and Chaetoceros calcitrans; Diet 4 – P. lutheri, S. costatum and C. calcitrans). During conditioning, samples of oysters were collected to evaluate condition index, gonadal development and biochemical composition. At the end of the conditioning period, oysters were induced to spawn to evaluate reproductive output (fecundity, fertilization rate and D‐larvae development). The diets had an impact on the gametogenesis process, energy storage and reproductive output performance, being the best results those obtained in broodstock fed with the diatoms‐predominant diets. However, those fed with diets majority flagellates had an unsuccessful performance. Holistic approaches incorporating all results in this study reveal and reinforce the idea that the diatom species used presented the nutritional requirements to C. angulata broodstock, being essential in the conditioning phase.     

Optimisation of larval culture of the mussel <Emphasis Type="Italic">Mytilus</Emphasis><Emphasis Type="Italic">edulis</Emphasis> (L.)

The blue mussel Mytilus edulis is a commercially important species whose fishery and culture generally relies on natural spat collection. Hatchery-production could provide an alternative source of seed, enabling reliable expansion of the industry. Mussel spawning and larval rearing trials were carried out to optimise elements of hatchery production. Culturing fertilised eggs at low density (20–200 eggs cm⁻²) rather than high density (400–720 eggs cm⁻²) significantly improved the quality of first veliger larvae and differences in this improvement were evident between the eggs from different females (maternal effects). Veliger larval growth at 17 or 21°C was significantly faster than growth at 14°C. Feeding veliger larvae an identical total ration either daily or at 2–3 day intervals did not significantly affect their growth. Different microalgal diets (1: Isochrysis sp. (clone T-ISO), 2: Chaetoceros calcitrans forma pumilus, 3: C. muelleri, 4: mixed Isochrysis sp. (clone T-ISO) and C. calcitrans f. pumilus, and 5: mixed Isochrysis sp. (clone T-ISO) and C. muelleri) were tested on veliger larval growth and mixed diets outperformed single-species diets.     

Growth,settlement and survival of Dicathais orbita (Neogastropoda,Mollusca) larvae in response to temperature,diet and settlement cues

The southern Australian whelk, Dicathais orbita, is a potential candidate for aquaculture, as both seafood and for bioactive compound production. Larval rearing experiments to determine the effects of temperature and diet on the growth and survival of D. orbita larvae under laboratory conditions comprised five different unicellular algal diets of two brown algal species; Isochysis galbana and Chaetoceros muelleri, two green algae; Tetraselmis seucica and Nannochloropsis oculata, and a mixture of all four strains for larvae maintained at 16 and 22°C. Absolute growth, specific growth rate (SGR) and survival were determined regularly. Larvae reared at 22°C on a mixed diet, or brown algae, performed significantly better than those reared on green algal diets alone. Preliminary trials with settlement cues were undertaken on different aged larvae to determine when larvae become competent. An array of natural cues (carrion, Xenostrobus pulex, adult mucus and Ulvella lens), as well as concentrations of KCl was tested. KCl(concentration of 20 mM) induced the greatest settlement, however, no larvae metamorphosed under the conditions provided. This study confirms long‐lived planktotrophic larval development for Dicathais orbita with higher development rates at the higher water temperatures. Further studies will optimize culture conditions and cues for settlement and metamorphosis.     

Diet trials on tehuelche scallop Aequipecten tehuelchus (d'Orb) larvae

Laboratory spawned one week old veliger larvaeof the tehuelche scallop, Aequipectentehuelchus (D'Orb., 1846), were reared topedivelger stage under three different dietaryregimes in order to determine the best algalcombination under standard hatchery conditions.Veligers were cultured at mean densities of 2.7larvae/ml. Larval growth and survival wereassessed on larvae fed the following dietarytreatments: (1) Isochrysis galbana(T-Iso)+ Chaetoceros calcitrans, (2)Pavlova lutheri + C calcitrans, and (3)P. lutheri + I. galbana T-Iso +Ch. calcitrans. The highest growth rateswere detected on larvae fed diets includingP. lutheri.     

Effects of single and combined microalgae on larval growth, development and survival of the commercial sea cucumber Holothuria spinifera Theel

The results of the study on the suitable algal feed for the mass rearing of holothurian larvae through hatchery system are presented. Auricularia larvae, after 48 h of fertilization, obtained from induced spawning of Holothuria spinifera, were fed with different algae Isochrysis galbana, Nanochloropsis salina, Pavlova lutheri, Tetraselmis chuii and Chaetoceros calcitrans as well as I. galbana+C. calcitrans to ascertain the effect of single and combined microalgal diet. The rate of feeding was 2 × 10⁴ cells larvae^–1 day^–1 for a period of 9–12 days. The growth rate of 59 μm day⁻¹ with 90% and 43 μm day⁻¹ with 100% occurrence of late auricularia in the larvae fed with C. calcitrans alone and I. galbana+C. calcitrans, respectively, indicated that C.calcitrans itself or in combination with I. galbana is the effective feed for the larvae of H. spinifera.     

Larval development and fatty acid composition of Ostrea edulis (L.) fed four different single diets from conditioning to pre‐settlement

Survival, growth and fatty acid composition of Ostrea edulis larvae (L.) fed four different single species, microalgal diets, Tisochrysis lutea (T), Chaetoceros neogracile (Cg), Skeletonema marinoi (Sm) or Tetraselmis suecica (Ts) from broodstock to pre‐settlement, were studied. Lower larval growth (5.5 μm to 6.5 μm/d) was recorded in progeny continuously fed single S. marinoi or T. suecica, whereas good growth was achieved with single T. lutea (7.8 μm/d). Larvae, originated from broodstock receiving Sm or Ts, exhibited growth compensation when fed a bispecific balanced diet (TCg). This did not occur when broodstock and larvae were fed Cg or T, for which single or mixed diets led to similar larval growth. Furthermore, survival was high (>90%) regardless of microalgal diet, except for larvae fed from broodstock to pre‐settlement T (53%) or Ts (2%). There were significant differences in 20:5 (n‐3) and 22: 6 (n‐3) contents in polar and neutral fractions of O. edulis expelled larvae dependent on broodstock diet, as well as throughout larval development, but no clear trend was apparent when comparing fatty acid (FA) relative composition of both fractions of O. edulis larvae fed different diets at release or prior to settlement. In contrast, such correlation occurred when FA was expressed in absolute content but exclusively for larvae‐fed single diets and was particularly noticeable between 22: 6 (n‐3) and growth and survival. In the present work, broodstock nutritional deficiencies have been revealed in O. edulis progeny, compensated thereafter by feeding the larvae a mixed diet, and in this balanced condition, no obvious relation with larval development indicators was found with main fatty acid contents.     

Effects of microalgal diets on larval growth and survival of Paphia malabarica chemnitz

The effects of food availability on the larval growth and survival of Paphia malabarica were studied in two experiments by feeding the larvae with six algal diets. Newly hatched larvae of P. malabarica were fed with six different marine microalgae species, singly and in a combination of two species. The best growth was with Isochrysis galbana and Nannochloropsis salina as a single species of diet. The nutritional value of single‐species diets was in the order of N. salina, I. galbana, Dicrateria inornata, Chaetoceros calcitrans, Tetraselmis gracilis and Dunaliella salina. Of the mixtures tested, 50%I. galbana/50%N. salina supported growth and metamorphosis equivalent to those of the I. galbana control.     

The nutritional effect of Isochrysis galbana and Chaetoceros muelleri cultured with different seaweed extracts on the larval development,growth and survival of the marine shrimp,Penaeus indicus

The microalgae Isochrysis galbana and Chaetoceros muelleri were cultured with seaweed extract (SWE) from six different seaweeds and each SWE was used either as a supplement or as an alternative media to conventional f/2 medium. Microalgae cultured with only the f/2 media acted as the control treatment. I. galbana and C. muelleri were then fed to Penaeus indicus larvae, either singly or in combination, for 8 days to evaluate its nutritional quality. Shrimp larvae fed on microalgae cultured in f/2 media supplemented with SWE from Ulva lactuca or Enteromorpha intestinalis moulted faster (P < 0.05) to the second mysis stage compared with the control. Survival, total length and growth rates were better in shrimp larvae fed on microalgae previously cultured in media supplemented with SWE. In general, shrimp larvae fed microalgae cultured entirely in SWE performed equally well compared with the control. Shrimp larvae fed on mixed microalgae (I. galbana + C. muelleri) showed significantly better growth, survival and development compared with larvae on either single microalgal diet. It was concluded that microalgae cultured with SWE could be used as a low‐cost alternative media in producing live food for the hatchery production of shrimp larvae.     

Oxygen consumption in trilobite larvae of the mangrove horseshoe crab (Carcinoscorpius rotundicauda; Latreille, 1802): effect of temperature,salinity, pH,and light–dark cycle

A set of feeding trials was carried out for different microalgal species and processed diets for the culture of the New Zealand pipi, Paphies australis. Five microalgal species (Isochrysis galbana clone T-ISO, Pavlova lutheri, Tetraselmis suecica, Chaetoceros muelleri, and Thalassiora pseudonana clone 3H) and three formulated diets (baker's yeast, wheat flour, and corn flour) were fed to spat, juvenile, and adult pipi for 21 days. Unfed pipi were used in the control group. The spat and juvenile pipi showed a major shell increase with I. galbana while the greatest wet weight increase was obtained with P. lutheri. The shells of adult pipi grew better with corn flour, and the P. lutheri-fed group obtained the greatest wet weight. Results of proximate analysis in adult pipi revealed that proteins and lipids were accumulated in the tissue for all fed groups, while carbohydrate levels were depleted in all treatments including the control group. It is suggested that the gonads have developed during the experiment.