Abstract: Utilizing a multidisciplinary, multi-state effort, the goal of this project is to enhance the commercialization of cobia aquaculture in the United States. Specifically, this project will focus on improving hatchery, nursery and growout of cobia in commercial aquaculture operations and collect information useful for managing wild stocks and evaluating the potential for stock enhancement of this species.

Use of dietary prebiotics to enhance growth, intestinal health, nutrient utilization and disease resistance of prominent warmwater and coldwater marine fishes

Abstract: The potential application of prebiotics in aquaculture has generated significant interest because of various benefits reported in terrestrial animals which may be conferred to warm- and cold-water fishes such as improved growth and enhanced immunity as well as increased nutrient availability and disease resistance. Prebiotics are non-digestible dietary ingredients that beneficially affect the host by selectively stimulating the growth and activating the metabolism of health-promoting bacteria such as Lactobacillus in the gastrointestinal (GI) tract, while limiting potentially pathogenic bacteria. Specifically, this project has executed in vitro and in vivo experiments to test the effects of several prebiotic compounds on juvenile red drum (Sciaenops ocellatus) and Atlantic salmon (Salmo salar) in which our researcher team is assessing growth performance, nutrient digestibility, intestinal health, and immune system competence of both species. Potentially, all cultured species could benefit from this type of nutritional research.

Research accomplishments to date: The initial findings of this research have been so significant that are now being expanded to nutritional trials with Pacific white shrimp Litopenaeus vannamei. In particular, the digestibility of energy and nutrient groups including organic matter, crude protein, and crude lipid have been shown to be significantly improved by the addition of certain prebiotics to the diet of red drum. Novel techniques such as denaturing gradient gel electrophoresis (DGGE) analysis, DNA sequencing and real-time polymerase chain reaction analyses also have been applied to characterize potential changes in GI tract microbiota as affected by prebiotic application (Figure 1). Dendrogram analysis of DNA relatedness from DGGE analysis has revealed divergence of enteric bacterial populations present in fish and shrimp subjected to different prebiotic treatments.

Figure 1. Extraction of intestinal contents, DNA quantification, PCR, DGGE, and amplicons

In addition to in vitro bacterial fermentations and in vivo feeding trials, the present research has also evaluated the capacity of fish under prebiotic treatment to perform productive physiological work such as resisting pathogens and toxic agents, growing, and swimming to stem currents and flee predators via automated respirometry (Fig. 2). Results from these assays are currently being analyzed.

Figure 2. Preparing red drum for an automted respirometry assay and data logger setup.

Moreover, a variety of non-specific immune response measurements including in situ pathogen challenges and immunological assays such as serum lysozyme, blood neutrophil oxidative radical production, and superoxide anion production of head kidney macrophages are being used to assess the immunocompetence of fish subjected to prebiotic treatment (Fig. 3).

Figure 3. In situ challenge with virulent Aeromonas hydrophila and neutrophil oxidative radical production assay.

Finally, the histological characterization of gastrointestinal (GI) tract tissues such as stomach, pyloric caeca and distal intestine are being performed to evaluate the potential effects of prebiotics on ultra-structural changes that would lead to functional modifications of the GI tract.

Future perspectives:
Results from the various evaluations in this project not only will provide insights concerning the underlying mechanisms associated with the effects of dietary prebiotics on the two fish species but also will allow a critical assessment of the potential for prebiotic supplementation in commercial aquaculture. In addition, this project will provide a unique opportunity to compare potential differences in the relative effects of dietary prebiotics on representative warmwater and coldwater carnivorous fishes and shrimp.

Alternative shellfish production methods, environmental interactions and regulatory compliance

Abstract: The goal of this project is to provide new information and tools that will allow the U.S. shellfish industry to continue to move forward in achieving the level of regulatory compliance necessary to operate sustainably and viably in the coastal environment. Specifically, this project will focus on the benefits and impacts of various types of shellfish production methods. The project is a continuation of an environmental and technical assessment of alternative methods to cultivate bivalve shellfish, such as oysters and clams.

Commercialization of bait shrimp farming based on specific pathogen-free stocks

Abstract: The goal of this project is to determine the economic feasibility of culturing two native species of shrimp used as bait by recreational fishermen throughout the southeast United States. Specifically, researchers will isolate and reproduce healthy broodstock from the wild, demonstrate commercial production for the two species, and conduct a market evaluation and financial feasibility analysis. The results will be transferred to the private sector through targeted outreach and demonstration projects. Ultimately, the results of this research could relieve pressure on wild shrimp stocks in the United States and provide an economic development opportunity for U.S. coastal communities.

Hawaii offshore aquaculture research project (HOARP) Phase V: Demonstration of sustainable offshore cage culture in Hawaii

Abstract: This project will identify and address the next steps in the successful demonstration of sustainable offshore aquaculture in the United States. Specifically, this phase of ongoing offshore aquaculture research will use existing open ocean aquaculture operations and research infrastructure in Hawaii to address critical scientific and regulatory issues in the genetic management of cultured stocks, examine disease transfer between wild and culture stocks, and advance the environmental modeling of cage effluents relative to the surrounding marine environment.

Assessment of environmental impacts of offshore cage culture

Abstract: The goal of this project is to determine the best way to detect the impacts of nutrient levels from open ocean aquaculture at the earliest stages so that potential problems can be identified and steps taken to minimize impacts. Specifically, this project will determine the impacts of two submerged fish cages on the surrounding environment in the coastal waters of Culebra, Puerto Rico. This research is important because ecosystem susceptibility to nutrient loads from submerged fish cages varies by location.

Building a superior striped bass: A genome map for accelerated selective breeding

Abstract: The goal of this project is to provide genetic information that will improve and expand the commercial production of striped bass, an important aquaculture species in the United States. Specifically, the project will use genetic markers to create the first genetic map for striped bass. A genetic map is required so that researchers can directly select for genetic traits underlying performance of cultured fish, a technique that will accelerate selective breeding to reduce production costs and allow the U.S. industry to compete successfully in world markets. This research will address major obstacles facing striped bass aquaculture in the United States and build on previous research on this species.

Offshore culture of California yellowtail (Seriola lalandi) - a multinational demonstration project supported by a well-established tuna farming infrastructure

Abstract: The goal of this project is to conduct a commercial-scale test on the feasibility of growing California yellowtail as a model for marine aquaculture. Specifically, the project will address the economic and production issues for yellowtail from egg to market size. California yellowtail is one of the prime candidates for the expansion of commercial aquaculture in the United States.

Demonstrating technological and economic feasibility of cobia (Rachycentron canadum) aquaculture from hatchery to market

Abstract: Although cobia is one of the prime candidates for expansion of aquaculture in the United States, there are critical issues that need to be resolved before commercial production of this species can move forward. Specifically, this project will examine several cobia production issues including hatchery techniques, disease control, production technology, and fingerling transfer. The project will emphasize technology transfer to industry.

Broodstock cobia (Rachycentron canadum) have been conditioned to naturally spawn at the University of Miami Experimental Hatchery (UMEH). Millions of eggs and larvae were produced for larval rearing trials using probiotics and a simplified live feeds regime. Research on probiotics use in live feeds continues. Several larval rearing trials were conducted with various degrees of success. Thousands of fingerlings were produced as “by-product” of the larval rearing research trials. Some were shipped to Puerto Rico to stocking Snapperfarm’s Aquapod submerged cage. Others are being used at the hatchery for nutritional, stocking densities and disease studies and a growout trial in a pond. These trails are ongoing.

We continue to collaborate with the industry and institutions for the development of marine fish culture in the U.S. Several shipments of cobia eggs and yolk-sac larvae were made to private companies and universities (e.g. Great Bay Aquaculture from New Hampshire and Virginia Tech from Virginia). Both GBA and VT conducted successful larval rearing runs using eggs and larvae from cobia broodstock from UMEH.

Diseases and nutrition are two areas identified as of major importance for the successful development of the cobia aquaculture industry in the US. Besides the ciliate protozoan parasites Amyloodinium, Cryptocaryon and Brooklinella, a bacterial disease caused by Photobacterium sp has been identified as a major potential threat for cobia during the fingerling, juvenile and adult stages. We continue to work in cooperation with UM veterinarians ad outside labs to perfect methods to identify, monitor and control disease outbreaks during both the hatchery and the growout stages.

There is continued development and improvement of juvenile shipping methodologies.

There is continued investigation into optimization of feeds formulation necessary for optimal growth and minimal dietary protein and lipid levels.

Background and preliminary investigations incorporating probiotics and microbial management into live feeds culture and marine finfish larval rearing continue.

We are currently conducting an experimental polyculture growout trial of cobia and conch in a saltwater pond at the UMEH. Cobia and conch juveniles were stocked in September of 2006; harvest is scheduled for April 2007. Results are highly promising, with both cobia and conch growing very well with no mortalities observed to date.

Snapperfarm has currently 3 submerged cages deployed and stocked with cobia for growout on its site off Culebra Island in Puerto Rico: two SeaStations and one Aquapod. This feat is per se a great accomplishment and an enormous success. The testing of the first Aquapod cage system by Snapperfram in Puerto Rico is ongoing with highly satisfactory results. It appears that the rigid geodesic design of the Aquapod system has solved one of the biggest problems faced by open ocean aquaculture operators in the tropics; losses due to predator (shark) attacks. As one of the primary objectives of this proposal (improved harvesting technology) Snapperfarm has successfully adapted a harvesting system for the first cobia harvests from an Aquapod. We are testing pneumatic stunners and bleeding to improve product quality and make the process more humane.

The main focus this year both at the hatchery and at the growout facility is on health and nutrition. A new bacterial disease has been identified affecting cobia juveniles (Photobacterium sp). We are currently considering testing vaccines on the smallest crop (75-100 grams juveniles) or in the next stocking early in the spring.

Nutrition trials are being carried out both at the hatchery and in the offshore cages. In the hatchery, we are comparing two different diets aiming at lowering protein levels and reducing fish meal use in aquafeeds for cobia. In the growout cages, three different diets are being tested (one per cage), all with different protein/energy ratios and levels of fishmeal substitution.

Snapperfarm is still working on the permits to expand its operations to 8 cages.

Environmental monitoring continues using a simplified method to detect nutrient buildup before it actually constitutes a problem. So far, results show that there are no significant or cumulative environmental footprint neither at the bottom nor at the water column of the site where the cages are deployed. Similar results were also obtained in the Bahamas. A manuscript describing these findings is being submitted for publication in a peer review journal (Marine Ecology Progress Series).

Eleven abstracts were submitted for oral presentations at the World Aquaculture Society Conference in Florence, Italy, in May 2006, Aquaculture America Conference in Las Vegas, Nevada, USA., in February 2006 and in San Antonio, Texas, in February of 2007.

The success of the research work conducted in association with these grant proposals has caught the attention of the national and international media. What follows are some of the highlights: In 2006, we were twice interviewed by NPR and were featured in several newspaper and magazine articles. Recently, ABC National News interviewed us at the UMEH and Snapperfarm and will run a piece in World News and Nightline sometime in December 2006. A crew from Outdoor Living Network (Outdoor Channel) visited Snapperfarm for interviewing and filming the farm. The show (World Wide Sport Fishing) is planned to air in February or March 2007. A photo of Snapperfarm also made the cut (as a solution to the problem) for a large 40 page global fisheries article that will run in National Geographic magazine in April 2007.

**Cobia Project Photos**
University of Miami maturation hatchery	Feeding cobia fingerlings	Cobia fingerlings swimming in tank
Harvesting cobia	Cobia swimming in cage	Cobia on ice after harvesting

Commercialization of black sea bass (Centropristis striata) aquaculture: nursery, growout and marketing

Abstract: This project will demonstrate black sea bass aquaculture in the United States. Specifically, the research will look at the feasibility of culturing black sea bass in land-based recirculating systems. Researchers will also conduct economic and market analyses as part of this study. Ultimately, the results of this research could bring another cultured species into the marketplace, creating jobs and economic opportunity for coastal communities.

Near commercial scale recirculating aquaculture systems (RAS) at coastal (UNCW, Wilmington) and inland (NCSU, Raleigh) locations in North Carolina are being assembled to demonstrate growout of hatchery-reared black sea bass (BSB) in seawater and in brackishwater at coastal and inland sites. At both locations, the RAS consists of four 16-m3 tanks and state-of-the-art RAS components to support biomass densities of > 60 kg/m3 (0.5 lb/gal). Operation of a saltwater fish production system in Raleigh, 145 miles away from the ocean, requires the development of a wastewater treatment system that completely renovates the wastewater effluent from the production system. GeoTube technology will be tested as a means of efficiently sequestering solid wastes from the RAS effluent, with minimal water (and salt) losses from the system.

A total of fifty thousand 1-g BSB fingerlings were produced by our industry partner, Great Bay Aquaculture (GBA, Portsmouth, New Hampshire). Another industry partner, Mid-Atlantic Aquatic Technologies (MAAT, Quinby, Virginia), has assembled two 15- ft. diameter recirculating seawater tanks for growout of BSB fingerlings. Three thousand fingerling BSB were shipped by air freight to MAAT’s facility during the week of Aug. 6, 2007. No mortalties were recorded following transport. Twenty thousand fingerlings were live-hauled from GBA’s hatchery in New Hampshire to Wilmington, NC on Aug. 8, 2007. Fish will be held in five 6-m3 tanks supplied with recirculating seawater until the end of August, when ten thousand fingerlings will be transported to NCSU (Dr. Tom Losordo) for stocking into the pilot-scale RAS for growout to market size at 20-24 g/L and 24 C. The remaining ten thousand fingerlings will be raised in 35 g/L seawater at UNCW.

At Skidaway Institute of Oceanography in Georgia, two 6,400-L tanks in a greenhouse were stocked with 100 hatchery-reared BSB. Using a geothermal cooling system from shallow water wells (depth ~ 25 m), seawater temperatures were maintained at 27-28 C during Jun-Jul 2007, while seawater temperatures in a control tank ranged from 30-33 C. To date, growth rates of hatchery-reared BSB in 6,400 L tanks fed juvenile tilapia have been higher than those fed commercial pellets (Skretting, Europa).

At UNCW, BSB fingerlings produced from eggs spawned in Jul 2006 were stocked in a RAS consisting of two 16-m3 tanks and reared through marketable stages. Each tank was stocked in Oct 2006 with 1,650 fish (mean wt = 27 g, age = 125 d post-hatching). On Jun 11, 2007 (695 d post-hatching), mean weight was 682 g (range = 328 -1,350 g). Survival was 75% and 79% in these two tanks, and biomass density reached 50 and 53 kg/m3. These fish are now being used for marketing trials described below.

Feeding trials were conducted to study the effects of replacing fishmeal protein by soybean meal. All diets were formulated to have the same crude protein (44%) and crude lipid levels (10%). Results indicated that fishmeal protein may be replaced by soybean meal (without methionine and lysine supplementation) at levels of up to 70% in the diet of juvenile BSB, without impairing survival or growth. A provisional patent has been obtained to protect this intellectual property. Fishmeal replacement by meat-and-bone meal and poultry-by-product meal at levels of at least 30% and 60%, respectively, were also successful, with higher substitution levels possible. These studies indicate that the BSB is an excellent candidate for commercial production using sustainable aquafeeds in intensive recirculating systems.

MARBIONC (Marine Biotechnology in North Carolina) is a private-public business incubator located at UNCW’s Center for Marine Science (UNCW-CMS). MARBIONC is the first economic development organization in the country to bring the first commercial crop of fully cultured BSB to the restaurant market. As part of the pilot-scale growout and marketing trial affiliated with the NOAA Marine Aquaculture Project, MARBIONC is now bringing samples of BSB, which have been spawned and raised in recirculating aquaculture systems at the UNCW-CMS Aquaculture Facility (Wrightsville Beach, NC) to restaurants and wholesalers in NC in exchange for completed questionnaires that will help MARBIONC evaluate market demand, price and potential. The large size and excellent quality of the fish have surprised and pleased local restaurants. Chefs from Tango du Chat, Hiro Japanese Steakhouse and Genki Sushi restaurants in Wilmington prepared a taste-testing for select media and on April 11, 2007. The following news articles appeared as results of these marketing trials:

We have developed a statistical model to estimate niche market demand for farm-raised BSB in North Carolina. The market niche is defined as restaurants selling fresh fish with average entree prices of $12 or more. Data are obtained via an in-restaurant, field sample survey of restaurant chefs and managers drawn from the population of all NC restaurants. A stratified sample (n ~ 90) of restaurants was selected from the restaurants in the niche. The sample was stratified by geographic region using three strata—coastal, central and mountain. The survey effort is underway; a graduate student is currently interviewing sampled restaurants across the state as part of his MSc thesis. As part of the survey, restaurant chefs will prepare fresh cultured BSB and compare it with their substitute fish.

A special session on “The Status of Black Sea Bass Aquaculture in the Eastern United States” was held at the World Aquaculture Society Meeting in San Antonio, Texas (March-April 2007).

Chef Paul Vroman prepares black sea bass April
11, 2007 for guests at the MARBIONC taste testing event at Tango du
Chat.  The fish were raised at UNCW's Aquaculture Facility in
Wrightsville Beach, NC.  ©C 2006 Workin4u, Inc.

Black sea bass fingerling harvest	Live haul of black sea bass	Great Bay Aquaculture 50,000 fingerlings

Cod culture: A sustainable opportunity for New England through diversification and use of existing, underutilized infrastructure and new technologies

Abstract: This project will leverage current research and the resources of industry partners to provide a road map for the establishment of sustainable Atlantic cod aquaculture throughout the northeast region of the United States. Specifically, the project will support hatchery technology development, develop improved organic feeds, and clarify the permit process for cod culture in near shore and open ocean environments. Atlantic cod are one of the prime candidates for expansion of aquaculture in the United States.

AQUACULTURE INFORMATION CENTER - DOC/NOAA

National initiative for aquaculture development and fishery enhancement of cobia, Rachcentron canadum