Commercial Aquaculture Facility Research Articles

First isolation of Carnobacterium maltaromaticum from farmed rainbow trout Oncorhynchus mykiss in Virginia.

Carnobacterium maltaromaticum is considered an emerging pathogen of salmonids in the United States and around the world. Bacterial cultures obtained from the posterior kidney and skin of moribund rainbow trout Oncorhynchus mykiss from a commercial aquaculture facility in Virginia, USA grew C. maltaromaticum, which was confirmed by additional phenotypic and molecular characterization. A presumptive diagnosis based on the clinical signs, necropsy observations, histopathology and bacterial cultures was bacterial septicemia due to C. maltaromaticum. This represents the first documentation of C. maltaromaticum in rainbow trout from Virginia.

Microplastics in surface water and tissue of white leg shrimp, <i>Litopenaeus vannamei</i>, in a cultured pond in Nakhon Pathom Province, Central Thailand

<abstract> <p>The presence of microplastics in commercially important seafood species is a new issue of food safety concern. Although plastic debris has been found in the gastrointestinal tracts of several species, the prevalence of microplastics in edible shrimp tissues in Thailand has not yet been established. For the first time, the gastrointestinal tract (GT), heptapancreas (HEP), muscle (MU) and exoskeleton (EX) of farmed white leg shrimp (<italic>Litopenaeus vannamei</italic>) from commercial aquaculture facilities in Nakhon Pathom Province, Thailand, were analyzed for microplastics (MPs). The number of MP items per tissue was 27.36±2.28 in the GT, 17.42±0.90 in the HEP, 11.37±0.60 in the MU and 10.04±0.52 in the EX. MP concentrations were 137.78±16.48, 16.31±1.87, 1.69±0.13 and 4.37±0.27 items/gram (ww) in the GT, HEP, MU and EX, respectively. Microplastics ranged in size from < 100 to 200–250 μm, with fragment-shape (62.07%), fibers (37.31%) and blue (43.69%) was the most common. The most frequently found polymers in shrimp tissue organs and pond water were polyethylene terephthalate (PET), polyvinyl acetate (PVAc) and cellulose acetate butyrate (CAB). Shrimp consumption (excluding GT and EX) was calculated as 28.79 items/shrimp/person/day using Thailand's consumption of shrimp, MP abundance and shrimp consumption. The results of the study can be used as background data for future biomonitoring of microplastics in shrimp species that are significant from an ecological and commercial perspective. MP abundance in farmed <italic>L. vannamei</italic> may be related to feeding habits and the source of MPs could come from the aquaculture facilities operations.</p> </abstract>

Microplastics in the tissues of commercial semi-intensive shrimp pond-farmed Litopenaeus vannamei from the Gulf of California ecoregion

The omnipresence of microplastics (MPs) in marine and coastal environments has attracted attention owing to their effects on various organisms, including humans. We present the first study of MPs in the gastrointestinal tract (GT), gills (GI), and exoskeleton (EX) of the farmed whiteleg shrimp Litopenaeus vannamei from commercial aquaculture facilities in northwestern Mexico that have operated semi-intensively for the last two decades. We found that the number of MP items per tissue was 7.6 ± 0.6 in the GT, 6.3 ± 0.9 in the GI, and 4.3 ± 0.9 in the EX, with an average of 18.5 ± 1.2 MP items per shrimp (1.06 items/g, wet weight [ww]). MP concentrations were 261.7 ± 84.5, 13.1 ± 1.8, and 2.6 ± 0.6 items/g (ww) in the GT, GI, and EX, respectively. Microplastics ranged from 30 to 2800 μm in size (360 ± 39 μm) with fibers (∼90.8%), filament-shape (∼93.4%), and transparent (∼47.7%) being the most common ones. Polyethylene (∼54.5%) and polyamide (∼24.2%) were the most commonly identified polymers, although polyesters (∼12.1%), polystyrene (∼6.1%), and nylon (∼3.0%) were also found. The abundance of MPs in farmed L. vannamei may be related to their feeding habits and the availability of MP sources in aquaculture facilities.

Thermal structuring of fish gelatin

Currently, fish gelatin is of special interest on the market of biopolymers due to its safety, natural protein composition, high quality indicators and compliance with ethno-cultural peculiarities of nutrition. It has individual features, including reduced thermostability. Physical modification that occurs under the influence of temperature and has an impact on the equilibrium process of globular and fibrillar conformation transitions was carried out in order to improve the functional and technological properties of fish gelatin. The object of the study was fish gelatin obtained using innovative technology from scales offish from the Volga-Caspian basin and commercial aquaculture facilities. Standard and original research methods were used in the study. Heat treatment was simulated depending on the temperature and duration of the process. Viscosity values variation of a 10% fish gelatin solution by 96.3% was caused by two factors. Influences caused by other factors are no more than 4 %. The possibility of structuring fish gelatin by high temperature treatment was determined. The rational mode of heat treatment is the temperature range from 125 to 130 °C. During the heat treatment at 135-140 °C, there is an increase in the duration of dissolution of fish gelatin and fragility of the plates along with a significant increase in the viscosity of solutions. Heat treatment of fish gelatin with residual moisture content of 10-16%, given the developed technological regimes and conditions, promotes the formation ofa polymer network (cross-linking), improving the consumer properties, performance of fish gelatin, and its hydrolytic stability.

Sperm quality of greater amberjack Seriola dumerili throughout the reproductive season and in response to GnRHa treatment with controlled release implants.

A wild-caught stock of greater amberjack Seriola dumerili reared in sea cages in two commercial aquaculture facilities in Greece was administered gonadotropin-releasing hormone agonist (GnRHa), loaded in controlled release implants, and was used in spawning induction experiments throughout the reproductive season. Sperm quality was evaluated using computer-assisted sperm analysis (CASA) before and after GnRHa administration and the extent of the spermiation period was determined. Males were in spermiation throughout the monitoring period from May 30 until July 18, at temperatures between 19 and 24 °C. However, lower sperm motility duration, density, and survival under cold storage were observed from early July onwards. Sperm quality did not recover after the end of spawning induction experiments in tanks and the return of the fish for 14-28 days to the sea cage in mid-July, which could be related to the high temperatures of this period. An improvement trend was observed in the quality of the milt collected on day 7 after a single GnRHa administration, but a significant decrease was observed on day 21 in sperm density, survival under cold storage, and straight line velocity (VSL). On the contrary, a double GnRHa administration spaced 14 days apart maintained the same sperm quality for a longer period of 29 days. Further spermiation enhancement experiments should be conducted in the future to describe in more detail the kinetics of sperm production after GnRHa therapy and its effects on sperm quality.

Diets of scaup occupying baitfish and sportfish farms in eastern Arkansas

Although not typically associated with eating fish, lesser scaup (Aythya affinis) and greater scaup (Aythya marila) have recently been reported consuming large quantities of bait- and sportfish produced on Arkansas commercial aquaculture facilities. During winters 2016–2017 and 2017–2018, we collected 529 lesser scaup and 19 greater scaup foraging on golden shiner (Notemigonus crysoleucas), fathead minnow (Pimephales promelas), goldfish (Carassius auratus), sunfish (Lepomis spp.), and other sportfish production ponds to investigate the diet composition of scaup. We compared lesser scaup diet between years, among temperature categories (Low, Medium, High), and among pond types using PERMANOVAs to investigate foraging dynamics. Lesser scaup diets differed between winters, and between Low and both Medium and High temperature categories. Only traces of fish were detected in scaup in winter 2016–2017, but fish comprised 18% of birds' overall diet in winter 2017–2018. Chironomidae was the most common prey item in lesser scaup during both winters, occurring in 86% and 68% of diets in winter 2016–2017 and 2017–2018, respectively. Chironomidae comprised 40% of lesser scaup diet by weight in winter 2017–2018, but 71% in winter 2016–2017. Similar to lesser scaup, Chironomidae was the most commonly occurring prey item in greater scaup, which occurred in 88% of the diets, or composed 74% of their overall diet. Fish comprised about 13% of the overall diet of greater scaup. We suspect that scaup increasingly exploited fish in colder winters, perhaps because of the birds' increased energy demands, prey availability, and ease of capture, or some combination of these.

Environmental Health Assessment Using Sentinel Species near Placencia Lagoon, Belize

Unexplained bird deaths discovered around Placencia Lagoon, Belize over a 2-year period sparked an investigation into the environmental health of the lagoon and two of its major tributaries. In this study, conducted from January 23 to February 28, 2018, we assessed avian health within two commercial aquaculture facilities, each with a substantial outflow into the lagoon; a shrimp farm and a tilapia farm. Birds were chosen as our study subjects not only because of previous bird deaths, but also as sentinel species to assess overall possible contamination. Both facilities had previously been affected by die-offs of their cultivated product. The variety of sampled bird species, both year-round and winter residents, fed on small fish, airborne insects, mud-dwelling invertebrates and/or plant material, i.e. seeds and fruits, thereby sampling air, soil and water as possible bioaccumulation vectors. We trapped birds in, or nearby outflow containment ponds which emptied into the lagoon. Additionally, we assessed avian health at two reference locations on Placencia Penninsula, not known for avian health problems. Birds from multiple families representing different ecological niches were captured using two net types. We conducted standard ornithological assessments, measured hematocrit, made an evaluation of ectoparasite load and types, and for shorebirds, examined fecal swabs for parasites. Measured values were compared to published data and a previously established database from data collected elsewhere in the Caribbean. For each of the major sites, an extensive period of evaluation was later followed with a shorter, second evaluation at each location. Except for a single, second-year, Brown Pelican (Pelicanus occidentalis) evaluated one day at the close of the study, 257 birds were found to be healthy on all parameters including hematocrit and parasite load. We observed that the pelican had not been present previously and inferred that its health problems were acquired at another site. This conclusion was corroborated by the concurrent discovery of dead or dying pelicans along the Belize coast near the end of this investigation.

Indicators of sustainability to assess aquaculture systems

Aquaculture is one of the fastest-growing food-producing sectors worldwide, making it desirable to assess the sustainability of aquaculture systems. The objective of this study was to develop a portfolio of quantitative indicators of economic, environmental and social sustainability to assess different aquaculture systems. The indicators were developed from 2003 to 2016, combining top-down and bottom-up methods, together with practical observations in experimental and commercial aquaculture facilities. A total of 56 economic (14), environmental (22) and social (20) indicators are proposed. Economic sustainability indicators reveal the degree of efficiency in using financial resources, the economic feasibility, resilience, and the capacity to absorb negative external costs and to generate funds for reinvestment. Environmental indicators reflect the use of natural resources, the efficiency in using resources, the release of pollutants and unused byproducts, and the risk of reducing biodiversity. Social sustainability indicators reflect the capacity to generate benefits for local communities, including jobs and food security, equitable income distribution, equality of opportunity, and inclusion of vulnerable populations. The indicators thus developed can be used on farm, regional, global or sectorial scales. They are quantitative, broad, scientifically sound, easy to understand and interpret, feasible to obtain on farms or on research stations, and permit comparison at different scales of space and time. Thus, they can be used to assess production systems and to compare different experimental treatments in research experiments. They also can be used by certifying organizations, investors, and policymakers. They allow performing diagnostics, identifying strengths and weaknesses, setting goals and determining actions, and assessing the effectiveness of actions and public policies.

Non-target effects of antifouling agents on mortality, hatching success, and acetylcholinesterase activity in the brine shrimp Artemia salina

Many commercial shipping, leisure crafts, and aquaculture facilities employ antifouling agents to control biofouling/biocorrosion by keeping their metallic hulls clear, but most agents have been known to cause negative effects such as pollution in coastal marine ecosystem. In this study, we measured the deleterious effects of three antifouling agents (i.e. tributyltin; TBT, diuron, irgarol 1051) on nauplii mortality, acetylcholinesterase (AChE, EC3.1.1.7) activity, and hatching success of cysts in the brine shrimp Artemia salina. Lethal concentration 50 (LC50) was measured using A. salina nauplii in time-course (i.e. 24, 48, and 72 h) to select proper concentrations for the suite of AChE assays. The 24 h-LC50 toxicities of three antifouling agents ranged for mortality were as follows: TBT 0.208 μg/L, diuron 10261 μg/L, and irgarol 1051 982 μg/L. Selected doses within the LC50 value of each antifouling agent significantly inhibited AChE activity for 24 h, and newly hatched nauplii were more sensitive than 48 h old nauplii. Furthermore, the exposure conditions dose-dependently reduced the hatching rate of A. salina cysts. We conclude that three antifouling agents tested in this study may have a toxic cholinergic effect on nauplii through AChE inhibition, in addition to ecotoxicity on cyst hatching.

Do young on-grown eels, Anguilla anguilla (Linnaeus, 1758), outperform glass eels after transition to a natural prey diet?

Summary Survival rates among European eels, Anguilla anguilla (Linnaeus, 1758), on-grown using a formulated diet in a commercial aquaculture facility, were compared with glass eels from the same cohort following their transition to a natural prey diet in the laboratory. Treatments included zero, 42-day, and 196-day periods of grow-out prior to 30-day experimental periods when eels were fed Chironomus spp. larvae (10 tanks, each containing 240-L water and 40 glass or 10 on-growing eels; 12:12 hr photoperiod; water temperature 18°C). All glass eels survived, compared to 87% (42-day) and 99% (196-day) for on-grown eels. Although the eels on-grown for 196 days had a high survival rate, they did lose weight. Farm-reared eels may have accumulated sufficient resources over the 196-days to survive the first 30 days after weaning from a formulated diet, but not for an additional 30 days (84% survival). Lack of superior survival rates among on-grown eels challenges the presumed benefits of releasing on-grown eels for population restoration.

Ontogentic shifts in genetic and maternal effects on length and survival in Chinook salmon (Oncorhynchus tshawytscha)

Understanding how the interplay between genetic and environmental factors changes over the lifetime of a species is critical when selecting broodstock to optimize production at each life stage and reduce bottlenecks in the production chain. We analyzed changes in environmental, additive genetic, and non-additive genetic contributions in growth and saltwater survival across multiple life stages of Chinook salmon (Oncorhynchus tshawytscha) in an aquaculture facility to assess the importance of each factor throughout life. We used a full-factorial breeding design and followed fish for their entire 3-year life cycle to quantify the dam and sire effect on growth and survival and partition these effects into the respective environmental and genetic components. We show for body size that maternal and non-additive effects are the most important drivers of larval size, explaining a total of 87% of total larval phenotypic variation, but decline with age. Additive genetic effects peak during the juvenile stage, explaining a maximum of 15% of the total variation in size, but are much less important at earlier and later life stages. We saw a similar pattern to saltwater survival—with non-additive effects high (42% of total variance explained) at the earliest stage measured and decreasing in later stages and additive effects playing little role. Unlike growth, there was little maternal influence on survival. Taken together, our results show that maternal and non-additive effects are important drivers of larval size but that additive effects may play a more important role with age. Non-additive effects explained the most phenotypic variance observed for survival, playing a much larger role than maternal or additive effects. Our results add to a growing body of literature suggesting careful crosses of select lines can lead to enhanced growth and survival and that these effects can be tailored to the life stages of most concern for a given system. In this way hatchery managers can best develop breeding lines for specific systems and these lines can have stable effects over many generations. Statement of relevanceThe enclosed manuscript is directly relevant to commercial aquaculture. The study was conducted in a commercial aquaculture facility and the questions we are asking relate to the effects of genetic and non-genetic (maternal) factors in Chinook salmon growth and survival in an aquaculture facility.

Molecular analysis of RNA1 and RNA2 sequences from a betanodavirus isolated from giant grouper (Epinephelus lanceolatus) in Australia

Betanodavirus infections have a significant impact through direct losses and trade restrictions for aquaculture sectors in Australia. The giant grouper, Epinephelus lanceolatus, is a high-value, fast-growing species with significant aquaculture potential. With subacute to chronic mortalities reported from a commercial aquaculture facility in northern Queensland, the viral nervous necrosis in the affected fish was confirmed using a RT-qPCR followed by virus isolation using the SSN-1 cell line. The RNA1 and RNA2 segments were sequenced and nucleotide sequences were compared with betanodavirus sequences from GenBank. Phylogenetic analysis revealed that both these sequences clustered with sequences representing red spotted grouper nervous necrosis virus genotype and showed high sequence identity to virus sequences affecting other grouper species. This is the first report confirming infection by betanodavirus in E. lanceolatus from Australia with successful isolation of the virus in a cell culture system, and analysis of nearly full length RNA1 and RNA2 sequences.

Ultrastructure and molecular phylogeny of Pleistophora hyphessobryconis (Microsporidia) infecting hybrid jundiara (Leiarius marmoratus × Pseudoplatystoma reticulatum) in a Brazilian aquaculture facility.

A microsporidian infecting the skeletal muscle of hybrid jundiara (Leiarius marmoratus × Pseudoplatystoma reticulatum) in a commercial aquaculture facility in Brazil is described. Affected fish exhibited massive infections in the skeletal muscle that were characterized by large opaque foci throughout the affected fillets. Histologically, skeletal muscle was replaced by inflammatory cells and masses of microsporidial developmental stages. Generally pyriform spores had a wrinkled bi-layer spore wall and measured 4·0 × 6·0 µm. Multinucleate meronts surrounded by a simple plasma membrane were observed. The polar filament had an external membrane and a central electron dense mass. The development of sporoblasts within a sporophorous vesicle appeared synchronized. Ultrastructural observations and molecular analysis of 16S rDNA sequences revealed that the microsporidian was Pleistophora hyphessobryconis. This study is the first report of a P. hyphessobryconis infection in a non-ornamental fish.

Water quality upstream and downstream of a commercial oyster aquaculture facility in Chesapeake Bay, USA

Oyster aquaculture is an expanding industry in the Chesapeake Bay. Oysters remove nitrogen (N) and phosphorus (P) from the water column through filtration and conversion of phytoplankton into shell and tissue, but also continuously excrete these same nutrients back into the water column as inorganic compounds readily available for plant or algal uptake. The objective of this study was to assess multiple water quality parameters upstream and downstream of a commercial oyster aquaculture facility in the mesohaline region of the Chesapeake Bay. Results of the study indicated a 78.4% average increase in total ammonia nitrogen (TAN) concentration and a 19.4% decrease in chlorophyll-a (Chl-a) concentration downstream of the facility. There was no significant change in the concentration of reactive phosphate (RP), nitrate–nitrogen (NO3−–N), or nitrite–nitrogen (NO2−–N) as water passed through the facility. It was determined that velocity of water through the facility had no influence on the change in TAN or Chl-a concentration from upstream to downstream of the facility. Increased reduction in Chl-a concentration from upstream to downstream was related to higher upstream concentrations of Chl-a. There was no correlation between increased rates of Chl-a removal and downstream TAN. Results of this study suggest that oyster aquaculture can significantly increase the amount of available inorganic nitrogen in the water column immediately downstream of a facility, independent of upstream availability of phytoplankton and flow velocity of water through the facility.

Nitrogen and phosphorus removal by the Algal Turf Scrubber at an oyster aquaculture facility

Integrated multi-trophic aquaculture is an aquaculture method by which waste of one species is used to produce another product. The purpose of this study was to determine rates of algal productivity using the inorganic nutrient waste from an oyster aquaculture facility, along with assessing the bioremediation potential of integrating an algal production system with the oyster aquaculture facility. Experimental-scale (1m2) Algal Turf Scrubber™ (ATS) systems were deployed at a commercial oyster aquaculture facility in Chesapeake Bay during summer 2012 and 2013 to determine algal productivity rates and assess the potential for remediation of inorganic nutrient release by the facility. Productivity rates of the ATS were high relative to previous studies, with a two-season average of 88.8galgae/m2/d. Total nitrogen and phosphorus removal rates by the ATS averaged 12.2g-N/m2/d and 0.25g-P/m2/d. An ATS with area of 640m2 would be needed to remediate all the nitrogen excreted by the oyster farm. A system of this size would produce 56.9kg of algae (dry weight), and remove 7.8kg of nitrogen and 151.6g of phosphorus per day during the summer growing season. The harvested algae is a resource that could potentially be used as biomass for biofuel production, food for livestock, or fertilizer.

Can fatty acid and mineral compositions of sturgeon eggs distinguish between farm-raised versus wild white (Acipenser transmontanus) sturgeon origins in California? Preliminary report

The objective was to investigate the potential of using fatty acid and mineral compositions of sturgeon eggs to distinguish their source, either farm-raised or wild fish. Trafficking of illegally obtained wild white sturgeon eggs is a major concern to the California Department of Fish and Game, but there is no forensic method to separate wild and farm-raised white sturgeon eggs. The extension of these findings in future work will be to use the fatty acid and mineral compositions as forensic indicators of caviar produced legally from farm raised sturgeon compared with illegal caviar produced from sturgeon poached from the wild. Samples (10) of sturgeon eggs were collected from a commercial aquaculture facility in the Sacramento Valley. Eggs from wild sturgeon (9) were obtained primarily from confiscations of illegally caught sturgeon by fish and game law enforcement personnel. The total lipid content of sturgeon eggs was analyzed for fatty acid composition. The most notable difference was the higher concentration (P<0.001) of C18:2n6 in farm raised eggs (6.5mg/100g total lipid) than wild eggs (0.6mg/100g total lipid) while other differences between fatty acids were smaller. Eicosapentaenoic acid (C20:5n3) was higher (P<0.02) in farm-raised (5.56mg/100g) than wild (4.49mg/100g). Docosahexaenoic acid (C22:6n3), C18:1 cis 9&10, and C20:4n6 were not different for origin of the eggs. Concentration of selenium was markedly higher (P<0.001) in eggs from wild sturgeon (10.0mg/kg dry weight) than farm-raised sturgeon (2.7mg/kg dry weight). Concentrations of iron, zinc, copper, phosphorus, sulfur, calcium, and potassium did not differ between farm-raised and wild eggs. Arsenic concentration in wild eggs was 3.3mg/kg dry weight whereas arsenic was not detected in the farm-raised eggs. Fatty acid and mineral compositions of eggs differed significantly between farm-raised and wild sturgeon and these should be investigated further as biological markers for forensic identification of caviar origin.

Winter and Summer Home Ranges and Core use Areas of Double-Crested Cormorants Captured near Aquaculture Facilities in the Southeastern United States

Numbers of Double-crested Cormorants (Phalacrocorax auritus) wintering in the southeastern United States have increased dramatically during the last 30 years concomitant with the rise of the aquaculture industry in this region. These cormorants commonly foraged at commercial aquaculture facilities and thereby came into conflict with farmers. Various interest groups are seeking ecologically sound strategies for minimizing the effects of burgeoning cormorant populations. Therefore, this study was conducted to estimate winter and summer home ranges of cormorants captured in the southeastern U.S. and determine whether age class, body mass, density of aquaculture facilities and availability of roost sites influenced size of these home ranges. Mean ± SE home range size and core use area of satellite transmitter-marked cormorants wintering in the southeastern U.S. from 1999 to 2001 were 17,490 ± 1,986 km2 (N = 37) and 1,550 ± 265 km2 (N = 37), respectively. Winter home range size was not affected by region, age class or body mass. Summer home range and core use area of marked cormorants was 30,547 ± 6,197 km2 (N = 6) and 3,124 ± 1,019 km2 (N = 6), respectively.

Effects of trophic levels (chlorophyll and phosphorous content) in three different water bodies (urban lake, reservoir and aquaculture facility) on gill morphology of Nile tilapia (Oreochromis niloticus)

Histological and ultrastructural analyses of gills were observed in Nile tilapia collected from three different waterbodies in southeast Brazil: an urban lake in a park in the city of São Paulo, a reservoir in a rural city, and a commercial aquaculture facility. These waterbodies were analyzed and classified as hypereutrophic, eutrophic, and supereutrophic, respectively, with 310.00, 94.00, 28.00 of phosphate ( μg L−1) and 65.49, 24.95, 12.83 of chlorophyll (μg L−1). A significant difference in the histological alterations index (HAI) was observed only in fish from the urban lake, with the presence of cell hypertrophy, hyperplasia, aneurism, and other alterations. When compared to the other groups, a large quantity of rodlet cells was also observed in the urban group. These results demonstrate the correlation of eutrophic states of water with gill morphology. Also discussed is the premise that large amounts of organic material dissolved in water can alter the morphology of the fish gills.

A computer vision system to analyse the swimming behaviour of farmed fish in commercial aquaculture facilities: A case study using cage-held Atlantic salmon

Knowledge of fish behaviour plays an important role in aquaculture farm management. Video systems are the most common and cost-effective way of observing behaviours in commercial aquaculture operations. However long term observation is not feasible due to a limited ability to analyse footage manually. This paper describes preliminary findings obtained via computer vision software that was developed to automatically analyse fish movement and behaviours in aquaculture sea cages. Results show that the system is capable of detecting fish shapes in video recordings and from these shapes quantifying changes in swimming speed and direction continuously throughout the day. Also variations between days were detected and these may have been associated with the daily shift in the tidal cycle. The system has the potential to act as an alarm to farm operators, informing them about unusual fish behaviours on a continuous, real-time basis. It also has potential to assist in the evaluation of fish welfare.

Linking R&amp;D Activities with Teaching: Water Quality Monitoring in Aquaculture as a Remote Laboratory Proxy for Environmental Studies

This work presents a system for on-line study purposes and for demonstrative operation of water quality monitoring based on previous full-scale trials in a commercial aquaculture facility under the scope of a R&amp;D project. This system is still under development, and was designed for sharing resources in R&amp;D activities and later in distance learning blended courses. An application developed in LabVIEW is responsible for receiving information from physical and chemical data (water level, flow, oxygen, temperature, pH, ORP and CO2) through a hardware interface. The acquired data are recorded in a Microsoft Access database that can be locally queried as desired. An IP camera allows students to observe the system in real-time. Students can log into the system and follow the real-time variations of a specific water quality parameter and the synergetic effects of these changes on the levels of other constituents. The water tanks contain no living beings in order to allow free adjustments of the parameters under study. The system description, data and remote access link is integrated in a basic course available in a Moodle® server. The goal of this course is to provide a stimulating interdisciplinary environment to a diverse group of undergraduate students, where critical research questions related to water are addressed. This system, unique in the area concerning with our knowledge, intends to contribute also to studentsâ?? training on data monitoring and analysis; and to nourish analytical skills and creativity of future scientists by encouraging potential graduate students to go further. Finally, this system allows the students to be familiar with the use of some new information technologies.