Shellfish Aquaculture Research Articles

Germplasm preservation for molluscan shellfish aquaculture and restoration

Germplasm preservation for molluscan shellfish aquaculture and restoration

Lessons from two high CO2 worlds – future oceans and intensive aquaculture

Exponentially rising CO 2 (currently ~400 μatm) is driving climate change and causing acidification of both marine and freshwater environments. Physiologists have long known that CO 2 directly affects acid–base and ion regulation, respiratory function and aerobic performance in aquatic animals. More recently, many studies have demonstrated that elevated CO 2 projected for end of this century (e.g. 800–1000 μatm) can also impact physiology, and have substantial effects on behaviours linked to sensory stimuli (smell, hearing and vision) both having negative implications for fitness and survival. In contrast, the aquaculture industry was farming aquatic animals at CO 2 levels that far exceed end‐of‐century climate change projections (sometimes >10 000 μatm) long before the term ‘ocean acidification’ was coined, with limited detrimental effects reported. It is therefore vital to understand the reasons behind this apparent discrepancy. Potential explanations include 1) the use of ‘control’ CO 2 levels in aquaculture studies that go beyond 2100 projections in an ocean acidification context; 2) the relatively benign environment in aquaculture (abundant food, disease protection, absence of predators) compared to the wild; 3) aquaculture species having been chosen due to their natural tolerance to the intensive conditions, including CO 2 levels; or 4) the breeding of species within intensive aquaculture having further selected traits that confer tolerance to elevated CO 2. We highlight this issue and outline the insights that climate change and aquaculture science can offer for both marine and freshwater settings. Integrating these two fields will stimulate discussion on the direction of future cross‐disciplinary research. In doing so, this article aimed to optimize future research efforts and elucidate effective mitigation strategies for managing the negative impacts of elevated CO 2 on future aquatic ecosystems and the sustainability of fish and shellfish aquaculture.

Preface: Recent Developments in Taxonomy and Biodiversity of Symbiotic Copepoda (Crustacea)-A Volume in Celebration of the Career ofProf. Il-Hoi Kim.

Symbiosis is one of the most successful modes of life displayed by aquatic organisms, as measured by the number of times it evolved and how many symbiotic species are presently in existence. Among the Crustacea copepods utilize an extraordinary range of hosts, occurring on virtually every phylum of marine macroinvertebrates and, jointly with the monogeneans, are the most speciose group of metazoan ectoparasites of marine fishes (Rhode 2005). Several species have a major impact on global finfish and shellfish aquaculture, causing significant effects on farm production, economic viability and sustainability (Shinn et al. 2015). Parasitism by copepods on other metazoans has evolved independently numerous times in the evolutionary history of animal life on Earth and has led to an exceptional diversity in morphologies, physiologies, life-strategies and habitat preferences of its members. Reflecting the diversity of hosts, copepods show an amazing variety of adaptations which secure infection of and survival on the hosts. Since the first descriptions of parasitic copepods occurring on fish by Linnaeus (1758) and the first report of a copepod utilizing an invertebrate host by Say (1818) (Clausidium caudatum (Say, 1818)) the number of described symbiotic copepods has seen a steady increase over a 200-yr period, culminating in a total of 5,306 valid species recognized today. About 38% of all described copepod species utilize either vertebrate (2,450 spp.) or invertebrate hosts (2,856 spp.), however, many host groups have not been thoroughly examined, and for this reason even approximate estimates of true species numbers are futile. Plotting the proposal of new species by decade (Fig. 1) shows a sharp rise since 1950 with 67% of the species having been described in the preceding 65 years. This period of exceptionally rapid progress can be attributed to a number of highly prolific investigators such as Arthur Humes, Il-Hoi Kim, Ju-shey Ho and Jan Stock who, single-handedly or in collaboration with other authors, described 698, 356, 290 and 246 species, respectively. Historically, the number of described copepod species parasitizing fish typically outnumbered those known to be associated with invertebrates. Only during the mid-1970s the species curves of both categories converged and during the last 30 years the discovery of new species associated with invertebrate hosts appears to progress more rapidly. Despite a significant drop in the number of specialists working on symbiotic copepods the steady addition of new taxa shows that the dynamism of their taxonomy is clearly set to continue.

Genetic Structure of Different Cultured Populations of the Pacific AbaloneHaliotis discus hannaiIno Inferred from Microsatellite Markers

ABSTRACT Pacific abalone Haliotis discus hannai is one of the most important species of shellfish aquaculture. The annual production of cultured abalone exceeded 100,000 t in 2013, and the Pacific abalone was the main farmed species. The genetic diversity of hatchery stocks of H. discus hannai in most areas of China, however, remains unknown. The exchange of Pacific abalone in China was not only among hatcheries but also between southern and northern areas, and the Japanese population was widely used for the production of seed. Both practices may have led to the production of mixed seeds, and the difference between populations may be not significant, which could result in inbreeding and loss of potentially valuable alleles. Therefore, it is necessary to assess the current genetic characterization of hatchery populations. For the analysis, a total of 10 populations were obtained from different hatcheries: Dalian, Qingdao, and Changdao in the northern coastal areas; and Xiapu, Lianjiang, Putian, Zhangpu, Ji...

Marine aquaculture and environment quality as perceived by Spanish consumers. The case of shellfish demand

Commercial fishing cannot in itself satisfy the growing demand for seafood, so Spanish aquaculture has expanded considerably over the past few decades. The country's great potential for aquaculture reflects the natural conditions Spain offers for farming marine species. Consumers have learned to identify products’ origins and hence to associate some regions with a certain quality. Although such association facilitates the marketing of distinctive products, it also involves some risks—including that marine pollution could result in consumers losing confidence in the quality or even the safety of seafood. This paper studies the demand of Spanish consumers for aquaculture shellfish as well as their perception of marine environment quality. The results show that consumer choices are affected by such perceptions and consumers would be willing to pay more for shellfish if doing so enabled implementation of a stronger program for guaranteeing food safety.

Integration of Next Generation Sequencing and EPR Analysis to Uncover Molecular Mechanism Underlying Shell Color Variation in Scallops.

The Yesso scallop Patinopecten yessoensis displays polymorphism in shell colors, which is of great interest for the scallop industry. To identify genes involved in the shell coloration, in the present study, we investigate the transcriptome differences by Illumina digital gene expression (DGE) analysis in two extreme color phenotypes, Red and White. Illumina sequencing yields a total of 62,715,364 clean sequence reads, and more than 85% reads are mapped into our previously sequenced transcriptome. There are 25 significantly differentially expressed genes between Red and White scallops. EPR (Electron paramagnetic resonance) analysis has identified EPR spectra of pheomelanin and eumelanin in the red shells, but not in the white shells. Compared to the Red scallops, the White scallops have relatively higher mRNA expression in tyrosinase genes, but lower expression in other melanogensis-associated genes. Meantime, the relatively lower tyrosinase protein and decreased tyrosinase activity in White scallops are suggested to be associated with the lack of melanin in the white shells. Our findings highlight the functional roles of melanogensis-associated genes in the melanization process of scallop shells, and shed new lights on the transcriptional and post-transcriptional mechanisms in the regulation of tyrosinase activity during the process of melanin synthesis. The present results will assist our molecular understanding of melanin synthesis underlying shell color polymorphism in scallops, as well as other bivalves, and also help the color-based breeding in shellfish aquaculture.

Geochemistry of phosphorus in sediment cores from Sishili Bay, China

This paper presents the distribution of total phosphorus (P), inorganic P (IP) and organic P in sediment cores from Sishili Bay, China. Their concentrations (μmolg−1) ranged from 15.04 to 21.59, 12.43 to 18.27 and 0.15 to 5.11, respectively, showing 87.6–96.9% of TP is IP. The distribution of the fractionation of IP , obtained by a sequential extraction technique, was 1.9–3.2% for soluble and loosely bound P (Ex-P), 8.5–13.1% for Al-bound from (Al-P), 7.4–9.5% for Fe-bound P (Fe-P), 5.0–12.4% for reductant-soluble P (Oc-P), 9.7–15.6% for CaCO3-bound P (ACa-P) and 45.9–54.6% for detritus P (Det-P). The P distribution and concentration was consistent with other Chinese coastal seas. No significant difference was found for the sedimentary P forms between scallop cultivation area and background area, indicating that shellfish aquaculture did not have significant effect on the depositional environment in the studied area, at least in case of P.

Efficacy of Probiotics in Preventing Vibriosis in the Larviculture of Different Species of Bivalve Shellfish

Hatcheries providing seed for bivalve mollusc aquaculture can suffer from disease outbreaks resulting in high losses of larvae. Previous research demonstrated the effectiveness of candidate probiotics Phaeobacter inhibens S4 (S4) and Bacillus pumilus RI06-95 (RI) in protecting the larvae of eastern oysters Crassostrea virginica, against bacterial challenge. In this study, the ability of this probionts in protecting larvae of other bivalve species, including northern quahog Mercenaria mercenaria, bay scallops Argopecten irradians, blue mussels Mytilus edulis, and razor clams Ensis directus, was investigated. Pretreatment of larvae with 106 colony forming units /ml probiotic S4 and a mixture of S4 and RI protected bay scallop larvae [relative percent survival (RPS): 69% ± 4%]. In pilot-scale hatchery trials, daily additions of candidate probiotics to the water of static tanks containing northern quahog or bay scallop larvae had no significant impact on larval growth and survival. Daily treatment of tanks with the probiotic RI led to significantly lower levels of Vibrio spp. levels in water and larvae compared with control on day 8 of the northern quahog hatchery trial (P < 0.05), but not for the bay scallop trial. Exposure of bay scallop larvae to S4 and a mixture of S4 and RI in the hatchery provided partial protection to experimental challenge (RPS: 55% ± 14% and 54% ± 4%, respectively). Treatment of northern quahog larvae with probiotics in the hatchery did not lead to increased protection to bacterial challenge. These candidate probiotic strains appear to have species-specific protective effects for bivalve larvae.

Growth, bioaccumulation and fodder potentials of the seaweed Sargassum hemiphyllum grown in oyster and fish farms of South China

Fish and shellfish aquaculture industries in Dapeng Cove, South China, have profound impacts on the coastal marine ecosystem in recent years. In this study, the local seaweed Sargassum hemiphyllum was introduced into oyster and fish farms as a biofilter during winter and early spring of 2013. Results showed that S. hemiphyllum grown in the fish farm suffered greater fouling and herbivory than these in the oyster farm. Thalli grown in both sites could achieve high growth rates during January and February; meanwhile, the specific growth rates for wet weight (SGRW) of seaweeds in the oysters farm at January, February and April samplings (7.16, 6.16 and 2.25%d−1, respectively) were all higher than those in the fish farm at the same sampling period (2.89, 3.19 and 0.90%d−1, respectively). The mean fresh-weight biomass increments for thalli grown in the oyster and fish farms were ~40 and 7 times, respectively, during the 4-month culture period. The N and P contents of S. hemiphyllum grown in both sites all varied significantly over time, and P contents of thalli in the oyster farm always higher than those of the fish farm at the same sampling period. The C, N and P bioaccumulation capacities of S. hemiphyllum cultured in the oyster farm were 15016.90±6241.78, 1112.45±459.81 and 134.69±55.46mgthallus−1, respectively, over the study period, which were all significantly higher than those in the fish farm (2457.46±1073.78, 180.27±75.23 and 13.69±5.88mgthallus−1, respectively). The nutritional composition of S. hemiphyllum in both sites were always comparable or higher than those of the seaweeds used as holothurian feed, and the heavy metal contents (Pb, Cd and Cr) were all well below the maximum allowable concentration for aquatic feed; thalli grown in the oyster farm were always with higher crude protein and fat contents, but lower heavy metal levels than those in the fish farm. We consider large-scale cultivation of S. hemiphyllum in Dapeng Cove can efficiently relieve the total environmental impact of aquaculture on the ecosystem of the whole bay, while give high yield of seaweed product with better quality. Statement of relevanceThis article provides useful information on the seaweed-based integrated multi-trophic aquaculture in fish and shellfish farms, and it can also give suggestion for the practice of large-scale cultivation of Sargassum and sustainable aquaculture in coastal area.

Nonnative Species in British Columbia Eelgrass Beds Spread via Shellfish Aquaculture and Stay for the Mild Climate

Nonnative species cause economic and ecological impacts in habitats they invade, but there is little information on how they spread and become abundant. This is especially true for nonnative species in native Zostera marina eelgrass beds in coastal British Columbia, Canada, which play a vital role in estuarine ecosystems. We tested how nonnative species richness and abundance were related to both arrival vectors and environmental factors in northeast Pacific eelgrass. Using correlation tests and generalized linear models, we examined how nonnative macroinvertebrates (benthic, epifaunal, and large mobile) and some algae species were related to arrival vectors (shipping and aquaculture) and environmental factors (climate variables, human population density, and native richness and abundance). We found 12 nonnative species, 50 % with known negative impacts within eelgrass habitats. For benthic organisms, both nonnative richness and abundance were strongly correlated with shellfish aquaculture activities, and not with shipping activity. For epifaunal nonnative richness and abundance, neither vector was significantly correlated. Climate (temperature and salinity) helped explain nonnative richness but not abundance; there was no relationship of nonnative richness or abundance to native species richness and abundance or population density. Results suggest that aquaculture activities are responsible for many primary introductions of benthic nonnative species, and that temperature and salinity tolerances are responsible for post-introduction invasion success. While aquaculture and shipping vectors are becoming increasingly regulated to prevent further international spread of nonnative species, it will be important when managing nonnatives to consider secondary spread from intraregional transport through local shellfish aquaculture and shipping.

Microplastic Ingestion by Wild and Cultured Manila Clams (Venerupis philippinarum) from Baynes Sound, British Columbia.

Microplastics, plastic particles <5mm, are an emerging concern in aquatic ecosystems. Because microplastics are small, they are available to many filter-feeding organisms, which can then be consumed by higher trophic level organisms, including humans. This study documents the quantity of microplastics present in wild and cultured Manila clams (Venerupis philippinarum). Three active shellfish farms and three reference beaches (i.e., non-shellfish farm sites) in Baynes Sound, British Columbia were chosen to examine the microplastic concentrations in wild and cultured Manila clams. Microplastics were isolated using a nitric acid digestion technique and enumerated from 54 clams (27 farmed and 27 non-farmed). Qualitative attributes, such as colour and microplastic type (fiber, fragment, or film) also were recorded. There was no significant difference (F=1.29; df=1,4; P=0.289) between microplastic concentrations in cultured and wild clams. Microplastic concentrations ranged from 0.07 to 5.47 particles/g (from reference beach and shellfish farm clams, respectively). Fibers were the dominant microplastic (90%); colourless and dark gray fibers were the most common colours observed (36 and 26%, respectively). Although this indicates that microplastics are definitely present in seafood consumed by humans, shellfish aquaculture operations do not appear to be increasing microplastic concentrations in farmed clams in this region.

Molluscan Shellfish Aquaculture and Production

Molluscan shellfish aquaculture provides high quality and high value seafood for human consumption, and shellfish provide environmentally beneficial ecosystem services, such as nutrient extraction and water filtration, to the environment in which they are grown. In the past five decades, global fisheries and aquaculture have grown steadily, and seafood consumption per capita has increased. Molluscan shellfish has traditionally been a major component of world aquaculture. Today, molluscs are cultured in 76 countries. This 8-page fact sheet describes molluscan shellfish aquaculture in the United States and worldwide and outlines molluscan shellfish aquaculture stages and methodologies. Written by Huiping Yang, Leslie N. Sturmer, and Shirley Baker, and published by the UF School of Forest, Fisheries, and Geomatics Sciences, January 2016. FA191/FA191: Molluscan Shellfish Aquaculture and Production (ufl.edu)

Optimization of growth requirements of marine diatomChaetoceros muelleriusing Response Surface Methodology

The marine centric diatom Chaetoceros muelleri has been widely used as live feed in fish and shellfish aquaculture due to its excellent nutritional properties. The growth of microalgae is affected by various nutritional and environmental parameters, and species specific optimization of these parameters is essential for the development of cost-effective biomass production process. In this study, the growth of C. muelleri, was optimized using response surface methodology (RSM). The variables nitrate, phosphate, silicate, temperature, pH, salinity and agitation speed were initially screened for biomass production in C. muelleri using Plackett–Burman experimental design, and it was found that nitrate, phosphate, silicate, temperature and pH significantly influenced the biomass production. These variables were further optimized by central composite design of RSM for biomass production and nutrient composition, and the medium was re-constituted accordingly to have 180 mg L−1 nitrate, 7.5 mg L−1 phosphate, 30 mg L−1 silicate, with optimum growth conditions of temperature at 31°C and pH 6.46. At the end of 10 days culture period under the above conditions, biomass, protein, lipid and carbohydrate significantly increased from 0.360 ± 0.01 mg L−1, 9.41 ± 0.02%, 18.11 ± 0.01%, 0.6 ± 0.02% to 1.16 ± 0.01 mg L−1, 11.02 ± 0.01%, 19.58 ± 0.01% and 0.77 ± 0.01% respectively. The biomass production of C. muelleri could be increased 3.2-fold with an improved nutrient profile by modifying the growth factors, the study thus offering an optimized process for biomass production of C. muelleri.

Direct setting of Crassostrea virginica larvae in a tidal tributary: applications for shellfish restoration and aquaculture

Direct setting of Crassostrea virginica larvae in a tidal tributary: applications for shellfish restoration and aquaculture

Managing marine mollusc diseases in the context of regional and international commerce: policy issues and emerging concerns.

Marine mollusc production contributes to food and economic security worldwide and provides valuable ecological services, yet diseases threaten these industries and wild populations. Although the infrastructure for mollusc aquaculture health management is well characterized, its foundations are not without flaws. Use of notifiable pathogen lists can leave blind spots with regard to detection of unlisted and emerging pathogens. Increased reliance on molecular tools has come without similar attention to diagnostic validation, raising questions about assay performance, and has been accompanied by a reduced emphasis on microscopic diagnostic expertise that could weaken pathogen detection capabilities. Persistent questions concerning pathogen biology and ecology promote regulatory paralysis that impedes trade and which could weaken biosecurity by driving commerce to surreptitious channels. Solutions that might be pursued to improve shellfish aquaculture health management include the establishment of more broad-based surveillance programmes, wider training and use of general methods like histopathology to ensure alertness to emerging diseases, an increased focus on assay assessment and validation as fundamental to assay development, investment in basic research, and application of risk analyses to improve regulation. A continual sharpening of diagnostic tools and approaches and deepening of scientific knowledge is necessary to manage diseases and promote sustainable molluscan shellfish industries.

A high resolution hydrodynamic model system suitable for novel harmful algal bloom modelling in areas of complex coastline and topography

Fjordic coastlines provide sheltered locations for finfish and shellfish aquaculture, and are often subject to harmful algal blooms (HABs) some of which develop offshore and are then advected to impact nearshore aquaculture. Numerical models are a potentially important tool for providing early warning of such HAB events. However, the complex topography of fjordic shelf regions is a significant challenge to modelling. This is frequently compounded by complex bathymetry and local weather patterns. Existing structured grid models do not provide the resolution needed to represent these coastlines in their wider shelf context. In a number of locations advectively transported blooms of the ichthyotoxic dinoflagellate Karenia mikimotoi are of particular concern for the finfish industry. Here were present a novel hydrodynamic model of the coastal waters to the west of Scotland that is based on unstructured finite volume methodology, providing a sufficiently high resolution hydrodynamical structure to realistically simulate the transport of particles (such as K. mikimotoi cells) within nearshore waters where aquaculture sites are sited. Model–observation comparisons reveal close correspondence of tidal elevations for major semidiurnal and diurnal tidal constituents. The thermohaline structure of the model and its current fields are also in good agreement with a number of existing observational datasets. Simulations of the transport of Lagrangian drifting buoys, along with the incorporation of an individual-based biological model, based on a bloom of K. mikimotoi, demonstrate that unstructured grid models have considerable potential for HAB prediction in Scotland and in complex topographical regions elsewhere.

Locally driven interannual variability of near‐surface pH and ΩA in the Strait of Georgia

AbstractDeclines in mean ocean pH and aragonite saturation state (ΩA) driven by anthropogenic CO2 emissions have raised concerns regarding the trends of pH and ΩA in estuaries. Low pH and ΩA can be harmful to a variety of marine organisms, especially those with calcium carbonate shells, and so may threaten the productive ecosystems and commercial fisheries found in many estuarine environments. The Strait of Georgia is a large, temperate, productive estuarine system with numerous wild and aquaculture shellfish and finfish populations. We determine the seasonality and variability of near‐surface pH and ΩA in the Strait using a one‐dimensional, biophysical, mixing layer model. We further evaluate the sensitivity of these quantities to local wind, freshwater, and cloud forcing by running the model over a wide range of scenarios using 12 years of observations. Near‐surface pH and ΩA demonstrate strong seasonal cycles characterized by low pH, aragonite‐undersaturated waters in winter and high pH, aragonite‐supersaturated waters in summer. The aragonite saturation horizon generally lies at ∼20 m depth except in winter and during strong Fraser River freshets when it shoals to the surface. Periods of strong interannual variability in pH and aragonite saturation horizon depth arise in spring and summer. We determine that at different times of year, each of wind speed, freshwater flux, and cloud fraction are the dominant drivers of this variability. These results establish the mechanisms behind the emerging observations of highly variable near‐surface carbonate chemistry in the Strait.

A HAB warning system for shellfish harvesting in Portugal

The development of sustainable shellfish aquaculture is highly dependent on the provision of reliable monitoring and predictive information on the occurrence of harmful algal blooms (HABs). The Portuguese HAB early warning system and shellfish closures presented here is a prototype, developed in the ASIMUTH project. It relies on weekly monitoring data composed of observations of HAB species and toxin concentrations within shellfish, and ocean circulation forecasts generated by an operational oceanographic model. The shellfish harvesting areas comprise coastal areas, estuaries+rías and coastal lagoons. The weekly bulletin characterizes the current shellfish closure situation and next week's forecasts for potentially impacted areas. The period analyzed ranged from 27 July 2013 to 17 March 2014, and describes the first skill assessment of the warning system. The forecast accuracy was evaluated, considering the number of forecasts that were verified to be correct the following week (85%) as well as the number of events not forecasted (false negatives, 12%) and those expected but did not occur (false positives, 3%). Variations were most visible in the first weeks of bulletin implementation and during autumn–winter months. The complementary use of field data, remote sensing and operational models led to more accurate predictions of blooms and range of the event.

Sequencing, De Novo Assembly, and Annotation of the Transcriptome of the Endangered Freshwater Pearl Bivalve, Cristaria plicata, Provides Novel Insights into Functional Genes and Marker Discovery.

BackgroundThe freshwater mussel Cristaria plicata (Bivalvia: Eulamellibranchia: Unionidae), is an economically important species in molluscan aquaculture due to its use in pearl farming. The species have been listed as endangered in South Korea due to the loss of natural habitats caused by anthropogenic activities. The decreasing population and a lack of genomic information on the species is concerning for environmentalists and conservationists. In this study, we conducted a de novo transcriptome sequencing and annotation analysis of C. plicata using Illumina HiSeq 2500 next-generation sequencing (NGS) technology, the Trinity assembler, and bioinformatics databases to prepare a sustainable resource for the identification of candidate genes involved in immunity, defense, and reproduction.ResultsThe C. plicata transcriptome analysis included a total of 286,152,584 raw reads and 281,322,837 clean reads. The de novo assembly identified a total of 453,931 contigs and 374,794 non-redundant unigenes with average lengths of 731.2 and 737.1 bp, respectively. Furthermore, 100% coverage of C. plicata mitochondrial genes within two unigenes supported the quality of the assembler. In total, 84,274 unigenes showed homology to entries in at least one database, and 23,246 unigenes were allocated to one or more Gene Ontology (GO) terms. The most prominent GO biological process, cellular component, and molecular function categories (level 2) were cellular process, membrane, and binding, respectively. A total of 4,776 unigenes were mapped to 123 biological pathways in the KEGG database. Based on the GO terms and KEGG annotation, the unigenes were suggested to be involved in immunity, stress responses, sex-determination, and reproduction. A total of 17,251 cDNA simple sequence repeats (cSSRs) were identified from 61,141 unigenes (size of >1 kb) with the most abundant being dinucleotide repeats.ConclusionsThis dataset represents the first transcriptome analysis of the endangered mollusc, C. plicata. The transcriptome provides a comprehensive sequence resource for the conservation of genetic information in this species and enrichment of the genetic database. The development of molecular markers will assist in the genetic improvement of C. plicata.

Homeopathy for mollusk aquaculture: Increased growth, survival, and protection of juvenile Catarina scallop Argopecten ventricosus against bacterial pathogen-challenge

Angel I. Campa-Cordova 1d, Pedro E. Saucedo 1e & Carmen Rodriguez-Jaramillo 1. 1 Centro de Investigaciones Biologicas del Noroeste ( CIBNOR ), La Paz, B.C.S., MEXICO. 2 Centro de Bioactivos Quimicos ( CBQ ), Universidad Central de Las Villas, Villa Clara, CUBA. 3 Instituto Nacional de Pesca ( INAPESCA ), La Paz, B.C.S., MEXICO. * Email: jmazon04@cibnor.mx Homeopathy for mollusk aquaculture: Increased growth, survival, and protection of juvenile Catarina scallop Argopecten ventricosus against bacterial pathogen-challenge