Progress 09/01/06 to 11/30/09
Outputs
OUTPUTS: Experiments to manipulate composition of biofloc communities including alteration of nutrients (P, Si), C/N ratio (molasses, dextrose, urea), light penetration (total exclusion, solids cropping), and solids control. Experiments were conducted in greenhouse raceways, outdoor tanks, and a pond. To evaluate how organic feeds can be integrated with the biofloc community, raceways were managed to produce predominantly heterotrophic or photoautotrophic communities. Two trials tested how organic diets produced by extrusion would impact shrimp production in these different environments. Seven diet experiments in small flow through tanks evaluated contribution of microbial biofloc integrated with an organic feed to impact shrimp growth. Waters from heterotrophic and the photoautotrophic raceways were each pumped through 16 tanks. The remaining 16 tanks received recirculated clear water. Experiments evaluated organic feeds vs fishmeal feeds in different microbial communities. Using deficiency diets we identified the nutrition (protein, HUFAs, or vitamins) that shrimp might extract from different microbial communities. The organic diet was tested under pond conditions as an extension demonstration project. Juvenile shrimp were stocked at low density in a privately owned pond and fed an extruded organic diet. Shrimp growth, water quality, and microbial community structure were monitored. The farmer sold to the public through partial harvests and a large final harvest. 32 outdoor tanks evaluated organic feeds in 8 biofloc communities. Treatments included high and low protein diets, high and low stocking densities, and high and low solids levels. Shrimp were grown in the 8 resulting communities. Parameters were measured to correlate biological and chemical dynamics with shrimp productivity within the different communities. A nitrogen mass balance model and a dynamic systems nitrogen model were developed. A study using outdoor tanks evaluated an organic extruded plant based feed vs a commercial fishmeal feed. Suspended solids were controlled by settling chambers or tilapia. Water quality, shrimp production, nutritional (fatty acid) and sensory (taste) attributes were measured. Studies evaluated whether specific biofloc algae and cyanobacteria could supply nutrition and whether shrimp could ingest and digest these microbes. Pure cultures were grown and incorporated into shrimp feeds or made available directly to shrimp. Results were disseminated through meetings of the SC Aquaculture Assoc., World Aquaculture Society, US Aquaculture Society, National Shellfisheries Assoc., 7th International Conference on Recirculating Aquaculture, Ferrum College Symposium, Grice Marine Lab Seminars, and SC Aquarium Public Forum. Testimony prepared for the Organic Aquaculture Symposium in conjunction with Fall 2007 NOSB meeting; Browdy served on expert panel. Talks for SCDNR Open House (2000 visitors), Waddell Mariculture Center Public Tours (1200 visitors). Local newspaper story on cooperative organic shrimp farming demonstration with private farmer. Research/training for 2 scientists, 1 postdoctoral fellow, 1 PhD and 2 MS students, and 9 college student internships. PARTICIPANTS: Individuals: John Leffler, PI, assisted former PI in design of project, now directing all aspects of project and supervising staff; Craig Browdy, former PI, designed, formerly directed, supervised all aspects of project; Jesus Venero, scientist, supervised on-site operations, nutritional studies; Jason Haveman, husbandry manager, supervised animal care and facilities management; Heidi Atwood, former shrimp program manager, supervised analytical and field measurements; Brad McAbee, former husbandry manager, supervised animal care and facilities management; Beth Lewis, lab manager, supervised analytical and field measurements; Andrew Ray, biologist, managed tank studies; Alisha Lawson, biologist, daily animal care and sample collection/analysis; Andrew Shuler, biologist, microbial community analysis; Jacob Richardson, biologist, daily animal care and sample collection/analysis; Stacy Stefan, lab technician, sample collection/analysis; David Brune, professor, modeling; Kendall Kirk, graduate student, modeling; Andrew Ray, graduate student, microbial community analysis; Megan Kent, graduate student, algal culture and nutrition studies; Amy Dickson, student intern, daily animal care and sample collection/analysis; Traci Holstein, student intern, daily animal care and sample collection/analysis; Elyse Walker, student intern, daily animal care and sample collection/analysis; Kristin Hoke, student intern, daily animal care and sample collection/analysis; Asher Dale, student intern, daily animal care and sample collection/analysis; Christopher Miner, student intern, daily animal care and sample collection/analysis; Emma Landherr, student intern, daily animal care and sample collection/analysis; Luis Vinatea, visiting Brazilian professor; Alfredo O. Galvez, visiting Brazilian professor; Mariane Pallaoro da Fontoura, Brazilian university student; Mauricio Emerciano, Brazilian university student. Partner organizations: Hollings Marine Laboratory, NOAA-NCCOS; Center for Coastal Environmental Health and Biomolecular Research, NOAA-NCCOS; Grice Marine Laboratory, College of Charleston; Agricultural Engineering Department, Clemson University; Collaborators: David Brune, Clemson University; MaryAnne Drake, North Carolina State University; Don Smith, Smith Shrimp Farm; Jon Ravenel, Yonges Island Mariculture Farm; Allen Davis, Auburn University; Robert Bullis, Advanced BioNutrition, Inc.; Tony Ostrowski, Oceanic Institute; Tzachi Samocha, Texas Agricultural Experiment Station; Gloria Seaborn, CCEHBR, NOAA-NCCOS; Jack Whetstone, Clemson University Agricultural Extension Service; Tim Markey, Zeigler Brothers, Inc., Susan Wilde, MRRI-SCDNR & USC. Provided research/training for two visiting Brazilian scientists, one post-doctoral fellow, one PhD student, two MS students. Internships provided for two undergraduate students and two visiting Brazilian university students. Training: Research/training for post-doctoral fellow; Research/training for PhD student; Thesis research/training for two MS students; Internships provided for 7 undergraduates, one graduate student; Volunteer assistance from one high school student. TARGET AUDIENCES: Provided educational talks for the South Carolina Aquaculture Association, World Aquaculture Society, U.S. Aquaculture Society, National Shellfisheries Association, 7th International Conference on Recirculating Aquaculture, the Ferrum College Environmental Symposium, Grice Marine Laboratory Seminars, and the South Carolina Aquarium public forum series. Testimony was prepared for the Organic Aquaculture Symposium in conjunction with the Fall 2007 NOSB meeting and C.L. Browdy served on the expert panel. Provided educational talks for SCDNR Marine Resources Division Open House (over 2000 visitors), SCDNR Waddell Mariculture Center Public Tours (over 1200 visitors), and a College of Charleston Aquaculture course. Interviewed by local newspaper for story on cooperative organic shrimp farming demonstration with private shrimp farmer. Provided research/training for two visiting Brazilian scientists, one post-doctoral fellow, one PhD student, two MS students, and summer internships for 7 undergraduate students and two visiting Brazilian university students. PROJECT MODIFICATIONS: Most of this project's goals and objectives were met following general procedures originally proposed. In order to improve transference of results to the private sector, shrimp densities for all experiments were increased to between 100 - 450 per cubic meter rather than the lower levels originally proposed. We also concentrated on greenhouse raceway systems since economically viable commercialization in the US will only be feasible in such superintensive systems rather than ponds. The dynamic systems modeling did not provide the anticipated insights, although the mass balance modeling demonstrated the apparent reduction of polluting nutrients through denitrification or volatilization. Two commercial producers with whom we were to interact closely went out of business and another private sector advisor left the industry. These individuals were no longer available for consultations.
Impacts
We found it very difficult to impose reliable, repeatable control over biofloc taxonomic composition. All communities were mixtures of heterotrophic and photoautotrophic organisms unless light was totally excluded, creating a heterotrophic system. Solids removal increased light penetration, increasing photoautotrophic structure, but did not control taxonomic composition. Nutrient loading from feed was the most significant factor altering this balance, driving systems into predominantly heterotrophic conditions. Within an established, stable system, biofloc composition can change dramatically and unpredictably without apparent effect on shrimp growth or water quality. Raceway experiments show that shrimp can grow in both heterotrophic and photoautotrophic communities using an organic plant based feed. No significant difference in shrimp growth or survival due to different biofloc communities. Feed produced by an extrusion vs pelleting permitted a higher growth rate while eliminating the need for chemical binders. Synthesis of diet experiments demonstrated that biofloc cannot replace or reduce prepared feeds, but will often improve growth when complete feeds are used. Neither heterotrophic nor photoautotrophic biofloc provides superior supplemental nutrition. Biofloc provides vitamins, but does not consistently provide DHA. Harmful flora may bloom in biofloc resulting in negative impacts on shrimp growth. Organic plant based diets can perform as well as fishmeal diets as long as a biofloc community is present. Shrimp in the pond demonstration project grew well and received considerable attention when local media ran a story that referred to the product as Green Shrimp and discussed the ecological and economic benefits. The first tank study demonstrated that biofloc community structure is resistant to management efforts. Potentially harmful algae appear and disappear, but their impact on shrimp growth and survival is unclear. Shrimp production was affected by stocking densities and solids removal improved shrimp performance. Mass balance nitrogen budgets showed a loss due to denitrification or volatilization when solids were controlled, reducing polluting effluents. The second tank study found no difference in shrimp production between the fishmeal and the organic plant diet. Solids removal resulted in greater shrimp production and lower nitrate and phosphate accumulation. Shrimp fed the plant diet were lower in EPA and DHA, but higher in LA; hence slightly lower quality. The n6:n3 fatty acid ratios for both were below 2. There were no flavor differences between shrimp fed the two diets, but the plant diet shrimp were more moist and fibrous. Experiments with pure cultures of important biofloc algal and cyanobacteria species incorporated into feeds displayed little nutritional benefit or inhibition from any of the organisms tested. Shrimp consumed and digested diatom species, but were unable to ingest or digest significant amounts of microbes less than 10 um. Nutritional benefit derived from biofloc is species specific or results from the aggregation of cells into larger particles.
Publications
- Ray, A.J., Shuler, A.J., Leffler, J.W., and Browdy, C.L., 2009. Microbial ecology and management of biofloc systems. In C.L. Browdy and D.E. Jory(Eds.), The Rising Tide, Proceedings of the Special Session on Sustainable Shrimp Farming. World Aquaculture Society, Baton Rouge, LA.
- Ray, A.J., Seaborn, G., Drake, M., Browdy, C.L., and Leffler, J.W. 2010. The effects of fish-based versus plant-based feeds and solids management on shrimp Litopenaeus vannamei flesh characteristics. World Aquaculture Society 2010 Annual Meeting Abstract Book, San Diego, CA. March 2010.
- Browdy C.L., Atwood, H., McAbee, B., Leffler, J., Stokes, A.D., Samocha, T., Losordo, T., Hanson, T.R., and Posadas, B.C. 2007. Research and development of sustainable super-intensive shrimp production systems: Perspectives on commercialization potential for US growers. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
- Browdy C.L., Seaborn, G., Atwood, H., Davis, D.A., Bullis, R.A., Samocha, T.M., Wirth, E., and Leffler, J.W. 2007. Comparison of pond production efficiency, fatty acid profiles and contaminants in Litopenaeus vannamei fed organic plant-based and fishmeal based diets. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
- Browdy, C.L, Venero, J. A., McAbee, B., Thomas, B.L., Stokes, A.D., Davis, D.A., and Leffler, J.W. 2008. Recent advances in sustainable super-intensive shrimp production system development and integration of microbial biofloc community structure with unique feeds to meet proposed USDA organic certification standards. World Aquaculture Society World Aquaculture Society Annual Meeting Abstract Book, Busan, Korea. May 2008.
- Browdy, C.L., Venero, J.A., Stokes, A.D., and Leffler, J.W. 2009. Enhancing competitiveness of U.S. shrimp aquaculture through innovative scientific research. National Shellfisheries Association 2009 Annual Meeting Abstract Book, Savannah, GA. March 2009.
- Browdy, C.L., Venero, J.A., Stokes, A.D., and Leffler, J.W. 2009. Superintensive biofloc production systems technologies for marine shrimp Litopenaeus vannamei: technical challenges and opportunities. In New Technologies in Aquaculture. Burnell, G. and Allan, G. (eds.). Woodhead Publishing, Cambridge, UK.
- Browdy, C.L., Ray, A.J., Shuler, A., and Leffler, J.W., 2009. Microbial ecology and management of biofloc systems. Asian-Pacific Aquaculture 2009 Abstract Book, Kuala Lumpur, Malaysia, November 2009.
- Haveman, J., Venero, J.A., Lewis, B.L., Lawson, A., Shuler, A., Browdy, C.L., and Leffler, J.W. 2009. Effect of photoautotrophic and heterotrophic biofloc communities on productivity of Pacific white shrimp Litopenaeus vannamei fed a plant-based diet in superintensive, zero-water exchange systems. National Shellfisheries Association 2009 Annual Meeting Abstract Book, Savannah, GA. March 2009.
- Holstein, T.E., Atwood, H.L., Venero, J.A., Browdy, C.L. and Leffler, J.L. 2008. Ecosystem energetics of a microbial biofloc community used to culture Pacific white shrimp Litopenaeus vannamei. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February, 2008.
- Kent, M.R., Browdy, C.L., Venero, J., Shuler, A., Seaborn, G., Battey, C. and Leffler, J.W. 2009. Isolating key contributors of microbial biofloc to Litopenaeus vannamei growth: how do biofloc taxonomic groups affect growth when provided as dietary supplements National Shellfisheries Association 2009 Annual Meeting Abstract Book, Savannah, GA. March 2009.
- Kent, M.R., Browdy, C.L., Venero, J., Shuler, A., Seaborn, G., Battey, C., and Leffler, J.W., 2009. Relative contribution of taxonomic groups within microbial biofloc communities to the growth of Litopenaeus vannamei when provided as dietary supplements. World Aquaculture Society 2009 Annual Meeting Abstract Book, Vera Cruz, Mexico. September 2009.
- Kent, M.R., Browdy, C.L., and Leffler, J.W. 2010. Consumption and digestion of suspended microalgal species common in biofloc culture systems by juvenile pacific white shrimp Litopenaeus vannamei. World Aquaculture Society 2010 Annual Meeting Abstract Book, San Diego, CA. March 2010. (In Press)
- Leffler, J., Atwood, H., McAbee, B., Brown, P., Morton, S., Wilde, S., and Browdy, C. 2007. Biofloc dynamics in super-intensive shrimp raceways: the good, the bad, the ugly. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
- Leffler, J.W., Seaborn, G., Lawson, A., Ray, A., Shuler, A., Thomas, B., Venero, J., Vinatea, L., Holstein, T. and Browdy, C.L. 2008. Evaluating the potential of microbial biofloc community monitoring techniques as management tools in superintensive zero-exchange shrimp culture systems. 7th International Recirculating Aquaculture Conference Abstract Book, Roanoke, VA. July, 2008.
- Leffler, J.W., Lawson, A., Ray, A., Seaborn, G., Shuler, A., Thomas, B., Venero, J., Vinatea, L., and Browdy, C.L. 2009. Monitoring tools for characterizing and managing microbial biofloc communities in superintensive zero-exchange shrimp culture systems. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009.
- Leffler, J.W., Venero, J.A., Ray, A.J., Lewis, B.L., Lawson, A., Haveman, J., and Browdy, C.L., 2009. Development of sustainable, commercially viable organic shrimp production by integrating plant based feeds with microbial biofloc community structure. National Shellfisheries Association 2009 Annual Meeting Abstract Book, Savannah, GA. March 2009.
- Browdy C.L., Seaborn, G., Atwood, H., Davis, D.A., Bullis, R.A., Samocha, T.M., Wirth, E., and Leffler, J.W. 2007. Comparison of pond production efficiency, fatty acid profiles and contaminants in Litopenaeus vannamei fed organic plant-based and fishmeal based diets. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
- Browdy, C., Seaborn, G., Atwood, H., Davis, A., Bullis, R., Samocha, T. and Leffler, J. 2007. Alternative approaches for removing fish meal and oils from farmed shrimp diets using plant and poultry meals and marine algal products. National Organic Standards Board Organic Aquaculture Symposium, Arlington, Virginia, November 27, 2007. http://ams.usda.gov//nosb/MeetingAgendas/Nov 2007/OralPresentations /BrowdyCPanelistPaperFeed11-07.pdf
- Leffler, J.W., Ray, A.J., Lewis, B.L., Venero, J.A., Vinatea, L., Shuler, A., and Browdy, C.L., 2009. Effects of an organic certifiable plant-based diet in conjunction with solids removal on the production of shrimp Litopenaeus vannamei in minimal exchange superintensive biofloc systems. World Aquaculture Society 2009 Annual Meeting Abstract Book, Vera Cruz, Mexico. September 2009.
- Leffler, J.W., Haveman, J., Durant, E., Lawson, A., and Weldon, D. 2010. Oxygen demand, ecological energetics and nutrient dynamics in minimal exchange, superintensive, biofloc systems culturing Pacific white shrimp, Litopenaeus vannamei. World Aquaculture Society 2010 Meeting Abstract Book, San Diego, CA. March 2010. (In Press)
- Leffler, J.W., Venero, J.A., Ray, A.J., Lewis, B.L., Lawson, A., Haveman, J., and Browdy, C.L. 2010. Managing the composition of biofloc communities to nutritionally supplement plant-based diets for Pacific white shrimp Litopenaeus vannamei. World Aquaculture Society 2010 Annual Meeting Abstract Book, San Diego, CA. March 2010. (In Press)
- Lewis, B.L., Browdy, C.L., Ray, A.J., Lawson, A., Shuler, A., Venero, J.A., Vinatea, L. and Leffler, J.W. 2009. Management of microbial biofloc communities using settling tank clarifiers in superintensive, zero-exchange shrimp production systems. National Shellfisheries Association 2009 Annual Meeting Abstract Book, Savannah, GA. March 2009.
- Ray, A., Shuler, A., McAbee, B., Seaborn, G., Wilde, S., Browdy, C.L. and Leffler, J.W. 2008. Influence of microbial community dynamics on the production of shrimp Litopenaeus vannamei in zero exchange biofloc systems. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February 2008.
- Ray, A.J., Browdy, C.L., Lewis, B.L., Venero, J.A., Vinatea, L., Shuler, A., and Leffler, J.W. 2009. Differences in shrimp Litopenaeus vannamei production and microbial dynamics as they relate to dietary protein source and solids management in minimal exchange superintensive culture systems. National Shellfisheries 2009 Annual Meeting Abstract Book, Savannah, GA. March 2009.
- Ray, A.J., Leffler, J.W., Seaborn, G., Venero, J.A., and Browdy, C.L. 2009. Effects of fishmeal versus soybean-based feeds and solids removal by settling tanks and tilapia on high-density shrimp Litopenaeus vannamei production in biofloc culture systems. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009.
- Ray, A.J., Lewis, B.L., Browdy, C.L., and Leffler, J.W. 2009. Comparing a fish-based feed and a plant-based feed with solids management in superintensive, minimal exchange shrimp (Litopenaeus vannamei) culture systems. Aquaculture, In Press.
- Ray, A.J., Shuler, A.J., Browdy, C.L., and Leffler, J.W. 2009. Microbial ecology and biofloc management of minimal exchange superintensive shrimp Litopenaeus vannamei culture systems. World Aquaculture Society 2009 Annual Meeting Abstract Book, Vera Cruz, Mexico. September 2009.
- Stokes, A.D., Leffler, J.W., Venero, J.A., and Browdy, C.L. 2009. Developing, designing, and operating a zero exchange bio-floc based shrimp production system. National Shellfisheries Association 2009 Annual Meeting Abstract Book, Savannah, GA. March 2009.
- Thomas, B., Leffler, J.W., Ray, A., Atwood, H., Lawson, A., McAbee, B., Shuler, A., Venero, J., and Browdy, C.L. 2009. Use of settling tank clarifiers to manage the microbial biofloc community in superintensive, zero-exchange shrimp production systems. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009.
- Vinatea, L., Galvez, A.O., Browdy, C.L., Stokes, A., Venero, J., Haveman, J., Lewis, B.L., Lawson, A., Shuler, A., Ray, A., and Leffler, J.W. 2009. Photosynthesis, water respiration and growth performance of Litopenaeus vannamei in a super-intensive raceway culture with zero water exchange: Interaction of water quality variables. Aquacultural Engineering. In Press.
- Vinatea, L., Galvez, A.O., Venero, J., Browdy, C.L., And Leffler, J.W. 2009. Oxygen consumption of Litopenaeus vannamei juveniles in heterotrophic medium with zero water exchange. Pesquisa agropecuaria brasileira 44(5):534-538.
- Venero, J.A., McAbee, B., Thomas, B., Browdy, C.L. and Leffler, J.W. 2008. Contribution of natural productivity of two microbial floc systems to growth performance and feed conversion rate (FCR) of Pacific white shrimp Litopenaeus vannamei fed diets with variable composition. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February, 2008.
- Venero, J.A., McAbee, B., Thomas, B., Leffler, J.W. and Browdy, C.L. 2008. Contribution of natural productivity of two different microbial floc systems on survival, growth performance, and feed conversion rate (FCR) of Pacific white shrimp Litopenaeus vannamei fed diets with variable composition. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February, 2008.
- Venero, J.A., Browdy, C.L., Haveman, J., Lawson, A., Lewis, B.L., Ray, A.J., and Leffler, J.W. 2009. Evaluation of the effect of a plant based diet on growth performance and FCR of Pacific white shrimp Litopenaeus vannamei raised either in a photoautotrophic or a heterotrophic hyper-intensive zero-exchange biofloc system. World Aquaculture Society 2009 Annual Meeting Abstract Book, Vera Cruz, Mexico. September 2009.
- Venero, J.A., Leffler, J.W., Galvez, A.O., Haveman, J., Lawson, A., Shuler, A., Thomas, B., Vinatea, L., and Browdy, C.L. 2009. Supplemental nutrition provided to pacific white shrimp Litopenaeus vannamei by natural productivity from either a photoautotrophic or a heterotrophic hyper-intensive zero-exchange biofloc system. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009.
- Venero, J.A., McAbee, B., Lawson, A., Thomas, B., Stokes, A.D., Browdy, C.L., and Leffler, J.W. 2009. Greenhouse-enclosed super-intensive shrimp production: alternative to traditional ponds in U.S. Global Aquaculture Advocate 12(1): 61-64.
- Wasielesky Jr., W., Atwood, H., Bruce, J., Kegl, R., Stokes, A. and Browdy, C.L. 2007. Effect of pH on growth and survival of Litopenaeus vannamei in a zero exchange super-intensive culture system. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
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Progress 09/01/07 to 08/31/08
Outputs
OUTPUTS: During Year 2, in order to evaluate how organic feeds can be integrated with microbial community composition, two raceways were managed to produce a no-light, totally heterotrophic community and a photoautotrophic/mixed community. Two trials were run testing how organic certifiable diets produced by different manufacturing processes that make possible a fully organic formulation would impact shrimp production in these microbially structured environments. Four diet experiments designed to improve on 2007 studies and aimed at better understanding the contribution of microbial biofloc to shrimp nutrition were conducted in 48 continuous flow-through tanks. Waters from the heterotrophic and the photoautotrophic raceways were each pumped through 16 tanks. The remaining 16 tanks were on a clear water, UV-filtered recirculating system. Experiments evaluated the effectiveness of organic feeds versus traditional fishmeal-based feeds in the different microbial communities. Through the use of deficiency diets we sought to identify the type of nutrition (protein, HUFAs, or vitamins) that shrimp might extract from the different microbial communities. The organic certifiable diet was tested under pond conditions as an extension demonstration project. Juvenile shrimp were stocked at low density in a privately owned shrimp pond and fed an extruded organic diet similar to the one fed in the raceway studies. Shrimp growth, water quality, and microbial community structure were monitored every two weeks. The farmer sold to the public through partial harvests and a large final harvest. Data from the 2007 tank study were analyzed and used to develop mass balance and dynamic system models based on the nitrogen cycle within these systems. Another study using 24 large outdoor tanks was conducted in 2008. Half of the tanks received a fishmeal-based feed and half received organically certifiable extruded feed. Suspended solids were reduced in one third of the tanks through settling chambers, one third used tilapia used as a filtering mechanism, and the remaining third had no filtration applied to them. In addition to a range of water quality and shrimp production parameters, sensory (taste) analysis of shrimp produced on typical fishmeal diets versus shrimp grown on organic plant-based diets will be conducted. Nitrogen and phosphorus mass balance budgets are being calculated. Provided educational talks for SCDNR Marine Resources Division Open House (over 2000 visitors), SCDNR Waddell Mariculture Center Public Tours (over 600 visitors); Aquaculture America Convention, World Aquaculture Society, 7th International Conference on Recirculating Aquaculture, Grice Marine Laboratory Graduate Student Seminar, College of Charleston Aquaculture course, local newspaper story on cooperative organic shrimp farming demonstration with private shrimp farmer. Provided research/training for two visiting Brazilian scientists, one post-doctoral fellow, one PhD student, two MS students. Internships provided for two undergraduate students and two visiting Brazilian university students. PARTICIPANTS: Individuals: John Leffler, PI, assisted former PI in design of project, now directing all aspects of project and supervising staff; Craig Browdy, former PI, designed, formerly directed, supervised all aspects of project; Jesus Venero, scientist, supervised on-site operations, nutritional studies; Jason Haveman, husbandry manager, supervised animal care and facilities management; Beth Thomas, lab manager, supervised analytical and field measurements; Andrew Ray, biologist, manager of tank pad studies; Alisha Lawson, biologist, daily animal care and sample collection/analysis; Andrew Shuler, microbial community analysis; Jacob Richardson, biologist, daily animal care and sample collection/analysis; Kristin Hoke, student intern, daily animal care and sample collection/analysis; Asher Dale, student intern, daily animal care and sample collection/analysis; Megan Kent, graduate student, algal culture and nutrition studies; David Brune, professor, modeling; Kendall Kirk, graduate student, modeling; Luis Vinatea, visiting Brazilian professor; Alfredo O. Galvez, visiting Brazilian professor; Mariane Pallaoro da Fontoura, Brazilian university student; Mauricio Emerciano, Brazilian university student. Partner organizations: Hollings Marine Laboratory, NOAA-NCCOS; Center for Coastal Environmental Health and Biomolecular Research, NOAA-NCCOS; Grice Marine Laboratory, College of Charleston; Agricultural Engineering Department, Clemson University; Collaborators: David Brune, Clemson University; MaryAnne Drake, North Carolina State University; Don Smith, Smith Shrimp Farm; Allen Davis, Auburn University; Tony Ostrowski, Oceanic Institute; Gloria Seaborn, CCEHBR, NOAA-NCCOS; Jack Whetstone, Clemson University Agricultural Extension Service; Tim Markey, Zeigler Brothers, Inc. Provided research/training for two visiting Brazilian scientists, one post-doctoral fellow, one PhD student, two MS students. Internships provided for two undergraduate students and two visiting Brazilian university students. TARGET AUDIENCES: Provided educational talks for SCDNR Marine Resources Division Open House (over 2000 visitors), SCDNR Waddell Mariculture Center Public Tours (over 600 visitors); Aquaculture America Convention, World Aquaculture Society, 7th International Conference on Recirculating Aquaculture, Grice Marine Laboratory Graduate Student Seminar, College of Charleston Aquaculture course, local newspaper story on cooperative organic shrimp farming demonstration with private shrimp farmer. Provided research/training for two visiting Brazilian scientists, one post-doctoral fellow, one PhD student, two MS students. Internships provided for two undergraduate students and two visiting Brazilian university students. PROJECT MODIFICATIONS: We conducted a low density pond demonstration grow out with a local private shrimp farmer as specified in the proposal. However economically viable commercialization of shrimp farming in the US will probably only be feasible in superintensive greenhouse raceways rather than ponds. As a result we continued to focus on raceway and tank studies with stocking densities of 300 animals per square meter rather than the lower levels originally proposed. We continued experiments to modify and manage different microbial biofloc communities using simple management protocols while improving the formulation of organically certifiable feeds designed to integrate with these communities. This led to another summer tank study not envisioned in the original proposal, but which has provided some of the best results to date demonstrating how properly formulated organic diets can be integrated with supplemental nutrition from the microbial community if the biofloc is well managed through a cropping regime.
Impacts
2007/09 - 2008/08. Results of the two raceway experiments show the economic potential of the organically certifiable, all plant-ingredient diet to grow shrimp under super-intensive conditions in greenhouse raceways. Both experiments were successful in producing market size shrimp under both sunlight photoautotrophic and completely dark heterotrophic conditions. Feed produced by an extrusion rather than a pelleting process permitted a growth rate of 1.2 vs. 0.9 g/wk respectively and makes feasible a truly organic feed. The small tank diet experiments demonstrated that with poor or deficient diets shrimp are able to benefit from both heterotrophic and photoautotrophic/mixed floc communities. However it is difficult to compensate for the benefits of a complete diet. Organically certifiable, plant-based diets performed as well as fishmeal diets as long as some form of biofloc community was present. Vitamin deficiencies are easily compensated when shrimp are grown in either type of biofloc community. Shrimp in the pond demonstration project had a growth rate of 1.1 g/wk and averaged >17 g. The project received considerable attention in the local general and aquaculture communities when the local media ran a story that referred to the product as "Green Shrimp" and discussed the ecological benefits and economic potential to the area of raising "organic" shrimp produced with feed prepared primarily with plant ingredients. Results from the 2007 large tank study demonstrated that microbial community structure is remarkably resistant to management efforts evaluated. Shrimp production was affected mainly by stocking densities, but solids removal through settling tanks tended to improve shrimp performance. Mass balance nitrogen budgets suggested a significant loss due to denitrification or volatilization, an important result for reducing nutrient effluents. The 2008 tank study demonstrated no significant difference in shrimp production between the fishmeal diet and the plant-based, organically certifiable diet. Suspended solids removal by settling chambers resulted in lower nitrate accumulation and significantly greater shrimp production. Tilapia did not cause noticeable changes in microbial community structure and did not impact shrimp production over the control systems.
Publications
- Browdy, C.L, Venero, J. A., McAbee, B., Thomas, B.L., Stokes, A.D., Davis, D.A., and Leffler, J.W. 2008. Recent advances in sustainable super-intensive shrimp production system development and integration of microbial biofloc community structure with unique feeds to meet proposed USDA organic certification standards. World Aquaculture Society World Aquaculture Society Annual Meeting Abstract Book, Busan, Korea. May 19-23, 2008.
- Browdy, C.L., Venero, J.A., Stokes, A.D., and Leffler, J.W. 2009. Superintensive Biofloc Production Systems Technologies for Marine Shrimp Litopenaeus vannamei: Technical Challenges and Opportunities. In New Technologies in Aquaculture. Burnell, G. and Allan, G. (eds.). Woodhead Publishing, Cambridge, UK. (in press)
- Leffler, J.W., Lawson, A., Ray, A., Seaborn, G., Shuler, A., Thomas, B., Venero, J., Vinatea, L., and Browdy, C.L. 2009. Monitoring tools for characterizing and managing microbial biofloc communities in superintensive zero-exchange shrimp culture systems. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009 (in press).
- Leffler, J.W., Seaborn, G., Lawson, A., Ray, A., Shuler, A., Thomas, B., Venero, J., Vinatea, L., Holstein, T. and Browdy, C.L. 2008. Evaluating the potential of microbial biofloc community monitoring techniques as management tools in superintensive zero-exchange shrimp culture systems. 7th International Recirculating Aquaculture Conference Abstract Book, Roanoke, VA. July 25-26, 2008.
- Ray, A.J., Leffler, J.W., Seaborn, G., Venero, J.A., and Browdy, C.L. 2009. Effects of fishmeal versus soybean-based feeds and solids removal by settling tanks and tilapia on high-density shrimp Litopenaeus vannamei production in biofloc culture systems. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009 (in press).
- Thomas, B., Leffler, J.W., Ray, A., Atwood, H., Lawson, A., McAbee, B., Shuler, A., Venero, J., and Browdy, C.L. 2009. Use of settling tank clarifiers to manage the microbial biofloc community in superintensive, zero-exchange shrimp production systems. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009 (in press).
- Venero, J.A., Leffler, J.W., Galvez, A.O., Haveman, J., Lawson, A., Shuler, A., Thomas, B., Vinatea, L., and Browdy, C.L. 2009. Supplemental nutrition provided to pacific white shrimp Litopenaeus vannamei by natural productivity from either a photoautotrophic or a heterotrophic hyper-intensive zero-exchange biofloc system. Aquaculture America 2009 Annual Meeting Abstract Book, Seattle, WA. February 2009 (in press).
- Venero, J.A., McAbee, B., Lawson, A., Thomas, B., Stokes, A.D., Browdy, C.L., and Leffler, J.W. 2008. Greenhouse-enclosed super-intensive shrimp production systems. Are they the sustainable alternative to traditional pond shrimp farming in the United States? Global Aquaculture Advocate (in press)
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Progress 09/01/06 to 08/31/07
Outputs
OUTPUTS: During Year 1 we conducted four diet experiments designed to better understand the contribution of microbial biofloc to shrimp nutrition. In one experiment shrimp were grown in photoautotrophic-dominated, heterotrophic-dominated, and clear water communities under several levels of conventional feed. A second study repeated this experiment with the inclusion of a plant-based diet made entirely from organically certifiable ingredients. The third diet study grew shrimp in the three types of microbial communities but modified the organic diet to evaluate whether shrimp could obtain supplemental protein or fatty acids from biofloc. In the fourth experiment biofloc from a heterotrophic-dominated community was incorporated directly into the organic diet formulation without supplemental fatty acids and fed to shrimp in clear water to evaluate its nutritional or growth promoting properties. A large experiment utilizing 32 outdoor tanks evaluated the efficacy of organic feeds in eight
different microbial communities. Two diets manufactured with organic certified ingredients provided high and low protein levels. These provided two distinct carbon-nitrogen ratios as inputs to the systems. Two levels of target stocking densities provided two distinct nutrient loading rates. Clarifiers on half of the tanks also altered microbial community structure by controlling suspended solids. Shrimp were grown in the 8 resulting communities for 13 weeks. All inputs, exports and shrimp harvest biomass were measured and analyzed. Shrimp growth and health were monitored weekly. Approximately 35 parameters were measured throughout the study to correlate biological and chemical dynamics with shrimp productivity within different microbial biofloc communities. One graduate student is using fluorescent microscopy, HPLC, and bacterial lipid analyses to describe the dynamics of the microbial communities in the outdoor tank experiment. His Masters thesis will relate shrimp productivity to
microbial community structure. Two undergraduate students (Florida, South Carolina) and a graduate student (Arizona) received internships to work on the tank study for 10 weeks during Summer 2007. Collaborating with David Brune at Clemson University, a PhD student is working with us on modeling the carbon and nitrogen fluxes in the biofloc systems from the outdoor tank experiment. The goal is to better understand the inputs, exports, and nutrient recycling dynamics in these systems in order to minimize or eliminate nutrient impacts on the external environment. We have developed and tested low energy airlift, gravity flow clarifiers to remove suspended solids from the biofloc systems as a means of guiding the microbial communities into configurations that increase shrimp productivity using organic diets. Preliminary results have been disseminated through talks to the Ferrum College Environmental Symposium, South Carolina Aquaculture Association, World Aquaculture Society annual
meeting, and the South Carolina Aquarium public forum series. Testimony was prepared for the Organic Aquaculture Symposium in conjunction with the Fall 2007 NOSB meeting and project PI will serve on the expert panel.
PARTICIPANTS: Individuals: Craig Browdy, PI, designed, directed, supervised all aspects of project; John Leffler, PD, assisted PI in design and implementation of project on daily basis, supervised staff; Jesus Venero, scientist, supervised on-site operations, nutritional studies; Heidi Atwood, lab manager, supervised analytical and field measurements; Brad McAbee, husbandry manager, supervised animal care and facilities management; Beth Thomas, biologist, daily animal care and sample collection/analysis; Jacob Richardson, biologist, daily animal care and sample collection/analysis; Alisha Lawson, technician, daily animal care and sample collection; Stacy Stefan, lab technician, sample collection/analysis; Andrew Ray, graduate student, microbial community analysis; Amy Dickson, student intern, daily animal care and sample collection/analysis; Traci Holstein, student intern, daily animal care and sample collection/analysis; Elyse Walker, student intern, daily animal care and sample
collection/analysis; David Brune, professor, modeling; Kendall Kirk, graduate student, modeling; Partner organizations: Hollings Marine Laboratory, NOAA-NCCOS; Center for Coastal Environmental Health and Biomolecular Research, NOAA-NCCOS; Agricultural Engineering Department, Clemson University; Collaborators: Robert Bullis, Advanced BioNutrition, Inc.; Allen Davis, Auburn University; OceanBoy Farms Inc; Tony Ostrowski, Oceanic Institute; Jon Ravenel, Yonges Island Mariculture Farm; Tzachi Samocha, Texas Agricultural Experiment Station; Gloria Seaborn, CCEHBR, NOAA-NCCOS; Andrew Shuler, MRRI-SCDNR; Jack Whetstone, Clemson University Agricultural Extension Service; Susan Wilde, MRRI-SCDNR Training: Research/training for post-doctoral fellow; Research/training for PhD student; Thesis research/training for MS student; Internships provided for two undergraduates, one graduate student; Volunteer assistance from one high school student.
TARGET AUDIENCES: Provided educational talks for SCDNR Marine Resources Division Open House, Ferrum College Environmental Symposium, South Carolina Aquaculture Association, World Aquaculture Society, South Carolina Aquarium Public Forum Series, Grice Marine Laboratory Graduate Student Seminar. Provided research/training for post-doctoral fellow, research/training for PhD student, thesis research/training for MS student, internships for two undergraduates and one graduate student, and volunteer opportunity for one high school student.
PROJECT MODIFICATIONS: In order to increase the ease of transferring the results of these studies directly to commercial operations, shrimp were stocked in the outdoor tank study at 100 and 300 per square meter rather than the lower levels originally proposed. We also sought to produce eight different microbial biofloc communities using simple management protocols rather than only the two communities originally proposed. Economically viable commercialization in the US will probably only be feasible in superintensive greenhouse raceways rather than ponds. We are seeking complementary funding beyond this grant to repeat and expand on this summer's tank studies to better achieve the goals of producing organic certifiable shrimp in greenhouse systems that are totally independent of coastal locations and that will require no discharge permits.
Impacts
The first diet experiment demonstrated that at 100% and 50% ration shrimp grew significantly better in both the photoautotrophic-dominated and the heterotrophic-dominated biofloc communities compared to the clear water community. This suggests that natural productivity contributed to their nutrition. In the second experiment shrimp raised on the organic diet grew just as well as those on the conventional diet when raised in the photoautotrophic community. However, in the heterotrophic and the clear water systems shrimp fed the organic diet had a significantly lower final weight than shrimp fed the conventional diet. The photoautotrophic microbial community, dominated by chlorophytes and diatoms, apparently supplements the nutritional value of the organic feed allowing it to produce results equivalent to conventional diets. Further analyses of the diets suggests that the photoautotrophic biofloc may supply the shrimp with long chain omega 3 fatty acids present in low
quantities in the organic feed. In diet study 3 shrimp fed the low protein diet gained significantly less weight than shrimp fed the other diets, either in the photoautotrophic or the heterotrophic water system demonstrating that the biofloc did not provide supplemental protein. For the other three diets (fish meal, organic, and low fatty acids) shrimp raised in the heterotrophic water system gained significantly less weight than those in either the photoautotrophic or in the clear water systems. Analyses of the microbial communities showed an abundance of a cyanobacterium, Synechococcus, in the heterotrophic community. This suggests that some microbial floc communities might retard shrimp productivity as well and promote it. Results from diet experiment 4 demonstrated that biofloc incorporated directly into fatty acid deficient feed permitted growth rates equivalent to the full formulation organic diet. Samples from the large outdoor tank experiment are still being processed and the
results analyzed. Preliminary evaluation of the nutrient dynamic model based on the tank data is planned for early December. In terms of new applied knowledge at this stage, we observed that the microbial communities are remarkably resistant to management efforts to alter their structure. However species compositions do change over time and these may have significant impacts on shrimp productivity. Potentially harmful algae, HABs, appear and disappear occasionally, but do not seem to adversely affect the shrimp. Development of a protocol that temporarily turned off aeration in order for in-situ dissolved oxygen probes to measure total system respiration (oxygen demand) and gross primary production proved to be an effective tool. The clarifier system designed and tested in the tank study proved to be very successful as a means to reduce organic solids rapidly and to maintain suspended solids levels within defined levels. This finding will have significant implications in reducing cost
for systems commercialization, thereby improving competitiveness.
Publications
- Browdy C.L., Atwood, H., McAbee, B., Leffler, J., Stokes, A.D., Samocha, T., Losordo, T., Hanson, T.R., and Posadas, B.C. 2007. Research and development of sustainable super-intensive shrimp production systems: Perspectives on commercialization potential for US growers. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
- Leffler, J., Atwood, H., McAbee, B., Brown, P., Morton, S., Wilde, S., and Browdy, C. 2007. Biofloc dynamics in super-intensive shrimp raceways: the good, the bad, the ugly. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
- Wasielesky Jr., W., Atwood, H., Bruce, J., Kegl, R., Stokes, A. and Browdy, C.L. 2007. Effect of pH on growth and survival of Litopenaeus vannamei in a zero exchange super-intensive culture system. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
- Holstein,T.E., Atwood, H.L., Venero, J.A., Browdy, C.L. and Leffler, J.L. 2008. Ecosystem energetics of a microbial biofloc community used to culture Pacific white shrimp Litopenaeus vannamei. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February, 2008 (in press).
- Ray, A., Shuler, A., McAbee, B., Seaborn, G., Wilde, S., Browdy, C.L. and Leffler, J.W. 2008. Influence of microbial community dynamics on the production of shrimp Litopenaeus vannamei in zero exchange biofloc systems. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February, 2008 (in press).
- Venero, J.A., McAbee, B., Thomas, B., Leffler, J.W. and Browdy, C.L. 2008. Contribution of natural productivity of two different microbial floc systems on survival, growth performance, and feed conversion rate (FCR) of Pacific white shrimp Litopenaeus vannamei fed diets with variable composition. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February, 2008 (in press).
- Venero, J.A., McAbee, B., Thomas, B., Browdy, C.L. and Leffler, J.W. 2008. Contribution of natural productivity of two microbial floc systems to growth performance and feed conversion rate (FCR) of Pacific white shrimp Litopenaeus vannamei fed diets with variable composition. Aquaculture America 2008 Annual Meeting Abstract Book, Orlando, Florida, February, 2008. (in press).
- Publications in 2007 may include significant contributions from other funding sources.
- Browdy, C., Seaborn, G., Atwood, H., Davis, A., Bullis, R., Samocha, T. and Leffler, J. 2007. Alternative approaches for removing fish meal and oils from farmed shrimp diets using plant and poultry meals and marine algal products. National Organic Standards Board Organic Aquaculture Symposium, Arlington, Virginia, November 27, 2007. http://ams.usda.gov//nosb/MeetingAgendas/Nov 2007/OralPresentations/BrowdyCPanelistPaperFeed11-07.pdf
- Browdy C.L., Seaborn, G., Atwood, H., Davis, D.A., Bullis, R.A., Samocha, T.M., Wirth, E., and Leffler, J.W. 2007. Comparison of pond production efficiency, fatty acid profiles and contaminants in Litopenaeus vannamei fed organic plant-based and fishmeal based diets. World Aquaculture Society Annual Meeting Abstract Book, San Antonio, Texas. February, 2007.
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