Growth performances for monoculture and polyculture of hatchery‐reared juvenile spotted babylon,Babylonia areolata Link, 1807, in large‐scale earthen ponds

This study was conducted to determine the feasibility of growing out hatchery‐reared spotted babylon juvenile (Babylonia areolata) in earthen ponds. The growth, survival and water quality for monoculture of spotted babylon were compared with the two polyculture trials with sea bass (Lates calcarifer) or milkfish (Chanos chanos). This study provided good results for growth and survival of spotted babylon in earthen ponds. The mean body weight gain of snails held in the monoculture was 5.39±0.08 g, and 4.07±0.16 and 4.25±0.11 g for those held in the polyculture with sea bass or milkfish respectively. Food conversion ratios (FCR) were 2.69, 2.96 and 2.71 for snails held in the monoculture and polyculture with sea bass and milkfish, respectively, and the final survival rates were 84.94%, 74.30% and 81.20% respectively. There were no significant differences in each parameter of water quality among the treatments but significant differences among the culture period were present (P<0.05). Salinity and total alkalinity showed the greatest changes during the culture period for all treatments. Seawater temperature, pH, dissolved oxygen, nitrite–nitrogen and ammonia–nitrogen gradually changed over the culture period for all the treatments. The present study indicated the technical feasibility for monoculture and polyculture of B. areolata to marketable sizes in earthen ponds.     

Effects of different feeding regimes on growth, survival and feed conversion of hatchery-reared juveniles of the gastropod mollusc spotted babylon Babylonia areolata (Link 1807) in flowthrough culture systems

The effects of feeding regimes on the growth, survival and feed conversion of hatchery-reared juvenile spotted babylon Babylonia areolata (Link) were assessed. Six continuous and discontinuous feeding regimes were fed at satiation to triplicate groups of snails in 200-L flowthrough (3.0 L h^–1) indoor rectangular tanks for 180 days. Shell length growth rates of juvenile B. areolata did not differ significantly (P > 0.05) between the various feeding treatments. Body weight gain and feed conversion of snails were not significantly different between various feeding treatments, nor were there significant differences in mean survival between any of the feeding treatments.     

Economic analysis of a pilot commercial production for spotted babylon, Babylonia areolata (Link 1807), of marketable sizes using a flow-through culture system in Thailand

This article examines the economic considerations involved in the production of spotted babylon (Babylonia areolata) in Thailand. A financial analysis of the construction and operating costs of a pilot commercial production of spotted babylon of marketable sizes is provided, based upon proven practical techniques and production data for a flow‐through growout system. The investment required for a spotted babylon growout hatchery producing 990 kg per year is estimated to be US$4528.8. The annual cost of operating such a hatchery is estimated to be US$4624.1. The cost of producing 990 kg of marketable‐size spotted bablyon with a survival rate of 95% is estimated to be US$4.91 per kg of snails produced. Cash flow analysis showed that a constant selling price of US$5.8 kg^?1 results in positive cash flow by year 4. The proposed enterprise is marginally feasible if cost can be considerably reduced by targeting production and integrating hatchery and growout operations.     

Pilot study on polyculture of juveniles spotted babylon, Babylonia areolata, with milkfish, Chanos chanos, to marketable sizes using large-scale operation of earthen ponds in Thailand

Growth, production and economic analysis was performed for the polyculture of juveniles spotted babylon, Babylonia areolata, and milkfish, Chanos chanos, to marketable sizes using a large‐scale production of earthen ponds in Thailand. The analysis was based on actual cost and production data from a pilot commercial‐scale farm. A total farm area of 0.8 ha was comprised of 0.3 ha grow‐out earthen ponds, a 0.4 ha seawater reservoir, and a 0.08 ha accommodation and office. Each pond was stocked with spotted babylon juveniles of 0.3 g initial body weight at a density of 200 snails m^?2, and they were harvested at a 7‐month period, at an average body weight of 4.6 g for a total yield per production cycle of spotted babylon and milkfish of 9875 and 6875 kg ha^?1 respectively. Based on farm data and harvest data used in this study, initial investment requirement was estimated to be $4837. The ownership cost and operating cost per production cycle were $2241 and $18 501 respectively. Total cost per production cycle was $20 742. The cost of producing spotted babylon marketable sizes in this grow‐out farm design was $6.56 kg^?1. The enterprise budgets based on the price of spotted babylon at a farm gate in 2003 of $9.00 kg^?1 results in gross return, net return, return to capital and management, and return on investment of $31 190, $10 448, $12 689 and 2.62 respectively. Milkfish was not calculated for any returns because they were less than marketable sizes.     

Growth and production of hatchery-reared juvenile spotted babylon Babylonia areolata Link 1807 cultured to marketable size in intensive flowthrough and semi-closed recirculating water systems

Hatchery‐reared juvenile spotted babylon Babylonia areolata (mean initial shell length 12.8 mm) were cultured intensively to marketable size in three 3.0 × 2.5 × 0.7 m indoor canvas rectangular tanks. The duplicate treatments of flowthrough and semi‐closed recirculating sea‐water systems were compared at an initial stocking density of 300 individuals m^?2 (2250 juveniles per tank). The animals were fed ad libitum with fresh carangid fish Selaroides leptolepis once daily. During 240 culture days, average growth rates in shell length and body weight were 3.86 mm month^?1 and 1.47 g month^?1 for the flowthrough system and 3.21 mm month^?1 and 1.10 g month^?1 for those in the semi‐closed recirculating system. Survival in the flowthrough system (95.77%) was significantly higher than that in the semi‐closed recirculating system (79.28%). Feed conversion ratios were 1.68 and 1.96 for flowthrough and semi‐closed recirculating systems respectively.     

Performance of the seaweeds Gracilaria salicornia and Caulerpa lentillifera as biofilters in a hatchery scale recirculating aquaculture system for juvenile spotted babylons (Babylonia areolata)

This study was conducted to determine the feasibility of using seaweeds as biofilters in a hatchery scale recirculating aquaculture system for juvenile spotted babylons (Babylonia areolata). Two seaweeds Gracilaria salicornia and Caulerpa lentillifera were used with three initial biomass levels of each species (280, 560 and 840 g wet weight m⁻³). Spotted babylon with an average initial shell length of 1.32 ± 0.01 cm and body weight of 0.37 ± 0.01 g was used with a stocking density of 300 snails m⁻². The experiment was carried out in triplicate over a period of 120 days. Results showed that seawater quality (water temperature, conductivity, salinity, pH, dissolved oxygen and total suspended solids) gradually changed with no significant differences between treatments throughout the experimental period, except alkalinity, total ammonia nitrogen, nitrite–nitrogen, nitrate–nitrogen and phosphate. Growth rates in weight and shell length of the spotted babylon cultured in all seaweed treatments used were not significantly different between seaweeds and density treatments, but significant differences in final survival rate of the spotted babylon were found between seaweed and density treatments. Growth rate and biomass gain of C. lentillifera were significantly higher than those of G. salicornia for all stocking density treatments. This study shows that Gracilaria salicornia and Caulerpa lentillifera can be used as biofilters for regulating water quality in a recirculating culture system for spotted babylons.     

Proteolytic enzyme activity of juvenile Asian sea bass, Lates calcarifer (Bloch), is increased with protein intake

The effect of high dietary protein intake on proteolytic enzyme activity of feeding juvenile Asian sea bass, Lates calcarifer (Bloch) was studied. Ninety fish [mean body weight ± standard error (SE) 304.62 ± 34.84 g] were randomly assigned to two dietary treatments, each with three replicates. In treatment 1, fish were fed by‐catch (Thunnus albacares) and in treatment 2, a formulated diet containing 50% protein. Proteolytic enzyme activity was determined in pyloric caecae and intestine at day 0, 7, 15, and 30. Initial proteolytic enzyme activity in sea bass ranged from 174 to 232 azocasein units (U^AC.) per mg of protein. After 7 days there was no significant difference in proteolytic enzyme activity of fish fed the two diets. However, a marked increase was observed in fish fed the formulated diet at day 15. After 30 days, the proteolytic enzyme activity in fish fed the formulated diet was threefold higher than that in fish fed the by‐catch diet. Fish fed the formulated diet had significantly higher total protein intake at day 7 than did fish fed by‐catch. Thereafter, a twofold weekly increase in the total protein intake was observed in both fish fed the by‐catch and formulated diets until day 30. These results suggest that a high dietary protein intake induces increased proteolytic enzyme activity in Asian sea bass.     

Effect of dietary supplementation of brewers yeast and nucleotide singularly on growth,survival and vibriosis resistance on juveniles of the gastropod spotted babylon (<Emphasis Type="Italic">Babylonia areolata</Emphasis>)

This study was undertaken to evaluate the use of brewers yeast and nucleotides as a growth promoter and to provide vibriosis resistance for the juveniles of gastropod spotted babylon (Babylonia areolata). Juvenile spotted babylon (0.3 g initial weight) were randomly distributed at a density of 50 snails in 45-L aquaria and fed a basic diet (40% crude protein) containing two incremental levels of 1 and 2% brewers yeast and nucleotides singularly for 4 months. After the feeding trial, snails from each treatment were challenged by pathogenic bacteria Vibrio alginolyticus given by intramuscular injection and kept under observation for 5 days to record clinical signs and daily mortality rates. Results indicated that the snails fed with diets supplemented with brewers yeast or nucleotides exhibited significantly greater growth than those fed the basic diet (P < 0.05) and significantly better food conversion ratios compared to snails fed the basic diet (P < 0.05). These results indicated that dietary supplementation of brewers yeast or nucleotides, at least at the tested dosages, enhanced spotted babylon growth. Supplementing the diet with 1% brewers yeast promises to provide appropriate resistance to V. alginolyticus.     

Combined effects of water exchange regimes and calcium carbonate additions on growth and survival of hatchery-reared juvenile spotted babylon (Babylonia areolata Link 1807) in recirculating grow-out system

To determine a suitable culture environment to maximize growth and survival, the hatchery‐reared juvenile spotted babylon, Babylonia areolata, were held in plastic rearing tanks at four calcium carbonate additions of 0, 100 and 300 g tonne^?1, and four water exchange regimes of 0‐, 15‐, 30‐ and 60‐day intervals in a recirculating grow‐out system for 120 days. The results clearly showed that growth was greatest between water exchange regimes of 15‐ and 30‐day intervals and all calcium carbonate additions, with water exchange regimes of 0‐ and 60‐day intervals resulting in poor growth. Final survival was highest between water exchange regimes of 15‐ and 30‐day intervals, and all calcium carbonate additions, with water exchange regimes of 0‐day intervals and all calcium carbonate additions resulting in high mortalities. This study showed that water exchange regimes had a stronger influence on the growth of juvenile B. areolata than calcium carbonate additions. It is recommended that B. areolata juveniles be maintained within the water exchange regimes range of 15–30‐day intervals and at calcium carbonate additions between 0 and 500 g tonne^?1, providing optimum conditions for production of this species in a recirculating grow‐out system.     

Effects of sodium diformate on growth performance,gut microflora,digestive enzymes and innate immunological parameters of Asian sea bass (Lates calcarifer) juveniles

This study was conducted to evaluate the effects of dietary sodium diformate (NaDF) on growth performance, gut microflora, digestive enzyme activities and immune response parameters of Asian sea bass (Lates calcarifer) juveniles. Fish with initial weight of 12.5 ± 0.4 g were fed with five experimental diets contained 0.0 (control), 5, 10.0, 15.0 and 20 g NaDF kg^?1 in triplicate for 6 weeks. Fish fed diet containing 5 g NaDF kg^?1 had significantly the highest final body weight and feed intake among different treatments. The gut total viable bacterial counts gradually decreased with increasing dietary NaDF level. Specific activity of chymotrypsin improved in fish fed diets administered with NaDF compared to the control group. Fish fed 5 g NaDF kg^?1 diet showed the highest serum lysozyme level among different treatments. The serum classical pathway activity of complement showed higher level in fish fed diets contained 5 and 10 g NaDF kg^?1 than other groups. According to break‐point regression method analysis, the optimum inclusion of dietary NaDF in L. calcarifer juveniles was estimated between 4.6 and 5.1 g/kg, when specific growth rate and feed conversion ratio were plotted against dietary NaDF levels.     

Quantitative immunoenzymatic detection of viral encephalopathy and retinopathy virus (betanodavirus) in sea bass Dicentrarchus labrax

Viral encephalopathy and retinopathy disease caused by betanodavirus, genus of the family Nodaviridae, affects marine, wild and farmed species including sea bass, one of the most important farmed species in Europe. This work describes a reliable and sensitive indirect ELISA assay to detect betanodavirus in biological samples using a polyclonal antiserum (pAb 283) against the 283/I09 virus strain, the most common red‐spotted grouper nervous necrosis virus (RGNNV) genotype in the Mediterranean area, and a capture‐based ELISA using a monoclonal antibody (mAb 4C3) specific to a common epitope present on the capsid protein. Using adsorbed, purified VERv preparation, the detection limit of indirect ELISA was 2 μg mL^?1 (3 × 10⁵ TCID50 per mL), whereas for capture‐based ELISA, the sensitivity for the antigen in solution was 17 μg mL^?1 (35 × 10⁵ TCID50 per mL). The capture‐based ELISA was employed to detect VERv in brain homogenates of in vivo infected sea bass and resulted positive in 22 of 32 samples, some of these with a high viral load estimates (about 1.1 × 10⁸ TCID50 per mL). The ELISA system we propose may be helpful in investigations where coupling of viral content in fish tissues with the presence of circulating VERv‐specific IgM is required, or for use in samples where PCR is difficult to perform.     

海鲈游泳续航时间和运动代谢规律研究

为研究海鲈(Lateolabrax japonicus)的游泳续航能力和游泳过程中的物质代谢规律,以深水网箱养殖的3月龄海鲈为研究对象,采用游泳续航时间和生化指标作为评测海鲈游泳能力和代谢规律的方法进行了试验。结果显示,海鲈的游泳续航时长为200 min,其续航能力强于大黄鱼而弱于美国红鱼。在游泳过程中,海鲈血糖浓度升高,但差异性不显著(P>0.05),肌糖原随着时间的增加显著减少(P<0.05),且肌糖原浓度在海鲈疲劳时接近于0。当鱼接近100%疲劳时,其肝糖原浓度也接近于0;当海鲈以不同疲劳程度游泳时,其肌肉乳酸脱氢酶浓度会显著升高(P<0.05)。表明海鲈的续航游泳过程伴随着无氧呼吸和有氧呼吸。     

Growout of hatchery-reared juvenile spotted babylon (<Emphasis Type="Italic">Babylonia areolate</Emphasis> link 1807) to marketable size at four stocking densities in flow-through and recirculating seawater systems

Hatchery reared juvenile spotted babylon, Babylonia areolata, were raised in canvas rearing tanks at four stocking densities (100, 200, 300 and 400 ind. m^–2) in flow-through and recirculating seawater systems until they reached the marketable sizes of 100–140 snails/kg. At all stocking densities, final increments in mean length and weight of snails held in flow-through systems were higher than those in recirculating systems, there was a significant effect (p < 0.05) of culture system on final length and weight. Mean (±SE) survival of snails held at 100 ind. m^–2 in the flow-through system was 100.0 ± 0.1% but was not significantly higher than survival in any other treatment (p > 0.05). Mean survival of snails held in the recirculating system was not significantly lower than at any stocking density in the flow-through system (p > 0.05).     

Compensatory growth response of European sea bass (Dicentrarchus labrax L.) under cycled starvation and restricted feeding rate

The compensatory growth response of the European sea bass (Dicentrarchus labrax) that faced cycling starvation and restricted ration was assessed. Juveniles (10.5 g) were stocked into 15 tanks at a density of 25 fish per tank. Five different feeding regimes were tested on triplicate groups of fish: C_Satiation: control fed for 60 days without deprivation, C_Restricted: 25% restricted feeding, S‐R: 1 day starvation then 4 days C_Restricted feeding, R‐F: 1 day C_Restricted feeding then 4 days C_Satiation feeding, and, finally, S‐F: 1 day starvation then 4 days C_Satiation feeding. The specific growth rate of fish in the C_Satiation (2.5 ± 0.06% day^?1), S‐F (2.5 ± 0.11% day^?1) and R‐F (2.4 ± 0.18% day^?1) were significantly higher than that of C_Restricted (2.2 ± 0.05% day^?1) or S‐R (2.0 ± 0.01% day^?1). Fish in S‐F group were able to achieve catching up with the C_Satiation. There was no significant difference in feed conversion rates but R‐F and S‐F consumed approximately 34% more feed than C_Satiation following the first re‐feeding day. Although, the highest lipid content was observed in C_Satiation (14.4%), S‐R (33.3% dry matter) had the highest water content compared with the C_Satiation and C_Restricted (37.8% and 36.9% dry matter respectively). In conclusion, it may be concluded that sea bass has rapid response to cycling starvation/re‐feeding and that a 25% restricted feeding ratio is insufficient to invoke a compensatory growth response in sea bass.     

Effects of conventional and organic feed on the mineral composition of cultured European sea bass (Dicentrarchus labrax)

European sea bass (Dicentrarchus labrax) is a widely consumed marine fish in Mediterranean areas, and different farming techniques are applied for fish culturing to satisfy the growing demand for seafood. The aim of this study was to investigate the effects of conventional and organic feed on the quality of cultured European sea bass (Dicentrarchus labrax) collected during the growth period. The concentrations of ash, moisture, essential macro‐elements (Ca, K, Mg, Na and P), micro‐elements (Co, Cr, Cu, Fe, Mn, Ni and Zn) and toxic elements (As, Cd, and Pb) were determined in feeds and in fillets of cultured fish. The results were compared to those obtained from wild sea bass. Results showed that the differences between organic diet‐fed and conventional diet‐fed sea basses varied in relation to the specific element measured and the growth period. The former showed higher concentration of Fe, Mg and Cr, and lower Na content. The amount of P, Na, Fe, Cu and Cr in wild sea bass was significantly (P ≤ 0.05) higher than that found in farmed fish. The levels of toxic elements in cultured sea bass were always within the allowed limit for fishery products. Wild samples had significantly (P ≤ 0.05) higher content of arsenic and lead than farmed sea bass. Cultured fish represent a valuable dietary source of essential macro‐ and micro‐elements. Controlled rearing systems and feedings were related to a decrease in the presence of some toxic metals in cultured fish compared with wild fish.     

Light intensity effects on early life stages of black sea bass, Centropristis striata (Linnaeus 1758)

The effects of four light intensities on growth and survival of first‐feeding stage black sea bass larvae Centropristis striata were investigated in a controlled‐environment laboratory. Fertilized eggs, obtained from LHRHa‐induced spawning of captive broodstock, were stocked (72 eggs L^?1) into twenty 15 L black tanks under light intensities of 100, 500, 1000 and 1500 lx, with five replicate tanks per treatment. The photoperiod was 12L:12D, the temperature was 20°C and the salinity was 35 g L^?1. Larvae were fed rotifers Brachionus rotundiformis from day 2 post‐hatching (d 2ph) at 5–10 rotifers mL^?1. Microalgae Nannochloropis oculata and Isochrysis sp. were added (1:1) daily to maintain a density of 300 000 cells mL^?1. Hatching success and larval growth and survival from d 2ph through d 15ph were monitored. Hatching success was 28–38% under all light intensities, and notochord length at hatching ranged from 2.8 to 3.0 mm, with no significant differences among treatments. By d 15ph, growth (mg wet weight) was significantly higher in the 1000 lx (0.914) and 1500 lx treatments (0.892) than in 100 lx (0.483), and a highly significant trend (P<0.01) towards increased survival with increasing light intensities was observed, from 1.3% at 100 lx to 13.9% at 1500 lx. Higher light intensities within the range of 100–1500 lx improved growth and survival of early larval black sea bass, suggesting that even higher light intensities may improve culture performance. This is consistent with conditions in shallow, near‐shore locations where eggs and larvae are distributed in nature.     

Effects of dietary calcium and phosphorus supplementation on the growth performance of juvenile spotted babylon <Emphasis Type="Italic">Babylonia areolata</Emphasis> culture in a recirculating culture system

A feeding experiment was conducted to determine the effects of dietary calcium and phosphorus, and the interaction between calcium and phosphorus, on the growth of juvenile spotted babylon, Babylonia areolata, cultured in a recirculating culture system. Nine isonitrogenous experimental diets supplemented with three levels of calcium (1, 4, and 7%) for each of three levels of phosphorus (1, 3, and 5%) were prepared using fish meal, squid meal, and shrimp meal as the main protein sources. Juveniles with an initial average body weight of 0.59 ± 0.09 g were fed to satiation once daily with one of the nine diets for 180 days. Absolute and specific growth rates were calculated for both shell length and whole wet body weight. Results showed that dietary calcium and phosphorus supplementation significantly affected the growth of juvenile spotted babylon (P < 0.05), but not survival and feed-conversion ratio. The specific growth rate in shell length (SGRL) ranged from 0.32 to 0.39% day⁻¹. No significant difference among phosphorus levels and no significant interaction between calcium and phosphorus in SGRL of the spotted babylon (P > 0.05) was found, but significant differences were observed among calcium levels, irrespective of phosphorus levels (P < 0.05). For 1 and 7% supplemental calcium, the spotted babylon had significantly higher SGRL than those fed diets supplemented with 4% calcium. However, the specific growth rate in body weight (SGRW) ranged from 0.91 to 1.19% day⁻¹ with no significant difference among calcium and phosphorus levels and no significant interaction between calcium and phosphorus (P > 0.05). Survival and feed-conversion ratio were not significantly affected by dietary calcium and phosphorus levels with ranges from 91.00 to 95.00% and 2.43 to 2.76, respectively. At the end of the experiment, shell abnormality of B. areolata was found for all feeding trials.     

Outbreak of hirame rhabdovirus infection in cultured spotted sea bass Lateolabrax maculatus on the western coast of Korea

In this study, we determined the cause of a disease outbreak in spotted sea bass, Lateolabrax maculatus reared in culture cages on the western coast of Korea in 2013. The major signs in the diseased fish exhibited were haemorrhaging on the membranes of the abdomen, gastrointestinal organs and opercular gills, as well as an enlarged spleen. No external morphological signs of infection were visible, except for a darkening in colour. No parasites or pathological bacteria were isolated from the diseased fish; however, epithelioma papulosum cyprini (EPC) cells inoculated with tissue homogenates from the diseased fish showed cytopathic effects (CPEs). Virus particles in the EPC cells were bullet‐shaped, 185–225 nm long and 70–80 nm wide, characteristic of Rhabdoviridae. Polymerase chain reaction analyses of homogenized tissues from the diseased fish and supernatants of cell cultures with CPEs indicated specific, 553‐bp‐long fragments corresponding to the matrix protein gene of the hirame rhabdovirus (HIRRV). Phylogenetically, the HIRRV phosphoprotein gene of spotted sea bass was more closely related to phosphoproteins from Chinese and Polish HIRRV strains than from other Korean strains. To our knowledge, this is the first report of HIRRV infection in cultured spotted sea bass.     

Effects of different feeding frequency on the growth, survival and feed conversion ratio of the Asian sea bass Lates calcarifer juveniles reared under hypersaline seawater of the Red Sea

The effects of several feeding frequencies of two, three and four times per day on Asian sea bass Lates calcarifer growth performance have been tested. Fish were reared under ambient Red Sea water conditions; these fish were fed diets containing 48% crude protein for 45 days. The present study was carried out at the Faculty of Marine Science (Abhor branch). The results show that fish population fed twice daily had significantly better growth with a mean body weight and daily weight increment of 59.04 and 1.31 g, respectively (P<0.05), than the other population fed three or four times daily. No significant differences were observed between fish fed two and three times daily in length gain and daily length increment. Growth in weight and length was increased gradually and no mortality was observed during the experimental period. In all the feeding trials, the body weight increased with an increase in length (R²=0.87 and 0.90). The feed conversion ratio (FCR) was significantly affected by feeding frequencies, with a significantly better FCR value of 2.43 in fish fed twice daily (P<0.05) compared with the other two populations fed three and four times daily. These results led to the conclusion that feeding two times daily would result in better growth and utilization of feed for the Asian sea bass L. calcarifer juvenile.     

Effects of different diets and seawater systems on egg production and quality of the broodstock Babylonia areolata L. under hatchery conditions

The broodstock of spotted Babylon snail, Babylonia areolata, were conditioned in indoor tanks under two seawater systems (static system and flow‐through system) and five types of foods (fish, shrimp, squid, green mussel and formulated diet). High survival and good feeding was found from broodstock conditioned in all treatments of seawater systems and diets. All broodstock showed active behaviour with no signs of stress as exhibited by active movement and feeding, protrusion of siphonal tube and constant egg laying throughout the experiment. Two‐way analysis of variance showed that there were no significant differences (P>0.05) in the total yield of egg capsules, size of egg capsules, size of newly hatched larvae and growth of larvae among broodstock B. areolata conditioned in the seawater system and diet treatments, but there were significant differences (P>0.05) in the frequency of egg capsule laying, number of fertilized eggs/embryos per capsule, total yield of fertilized eggs/embryos and final survival of larvae among broodstock B. areolata conditioned in the diet treatments. We present initial evidence that the seawater system had a stronger influence on the egg production and quality of broodstock B. areolata than conditioning diets.