2004 Annual Report 1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? This report serve to document research conducted under a Specific Cooperative Agreement between ARS and Mississippi Agricultural and Forestry Experiment Station. Additional details of research can fe found in the report for the parent CRIS 6402-31000-007-00D, "Improve Production Efficiency in Aquaculture". Spending on seafood by United States' consumers presently stands at over $55 billion annually. Demand far exceeds domestic production, generating a $7 billion dollar annual trade deficit-the third largest U.S. trade deficit after petroleum and automobiles. Increasing seafood production from wild fisheries to meet this demand and offset the deficit is not possible because most national and global wild-catch fisheries are fully exploited. The only way to close the enormous trade deficit in seafood and reduce America's dependence on foreign products is to dramatically increase domestic aquaculture production. The channel catfish is the most important aquaculture species in the United States. In 2003, just over 300 million kg of channel catfish were processed, representing over half the total United States aquaculture production. Catfish aquaculture has generally been a profitable and rapidly expanding industry in the southeastern United States. However, yield has not increased in recent years and profits have decreased. We have addressed these problems through a multidisciplinary program focused on improving the efficiency of catfish production. The overall goal of this project is to develop management practices that provide greater control of production activities in channel catfish aquaculture. Specific areas of research have been identified through interactions with industry, extension service representatives, and research personnel in other disciplines and other states. This research directly addresses several components of the National Program 106 Aquaculture action plan such as: Section E (Early Life Stage Development and Survival) of the REPRODUCTION AND EARLY DEVELOPMENT component, Section B (Water Use and Reuse) and Section C (Effluent Management Control) of the SUSTAINABILITY AND ENVIRONMENTAL COMPATIBILITY OF AQUACULTURE component, Section D (Off-flavor Delayed Harvesting) of the QUALITY, SAFETY AND VARIETY OF AQUACULTURE PRODUCTS FOR CONSUMERS component and Section E (Live Aquatic Animal Handling, Transport, and Inventory) of the AQUACULTURE PRODUCTION SYSTEMS component. All objectives are focused on improving production efficiency to improve the profitability of channel catfish farming. Application of successful research results will assure an inexpensive and dependable supply of seedstock for the industry, reduce environmental impacts and water use, reduce production constraints due to environmental off-flavors, and improve fish harvest efficiency. The overall benefits of this project will be the development of techniques to enhance economic performance, improve global competitiveness, and allow domestic aquaculture to reduce dependence on imports to meet the U.S. demand for seafood. 2.List the milestones (indicators of progress) from your Project Plan. The initial ARS Project Plan for this project will undergo OSQR review in August, 2004. As such, this report addresses objectives above rather than specific milestones. In the past year the program had the following objectives: Objective 1: Increase the reliability, efficiency, and cost-effectiveness of catfish fry production through the use of new and improved technologies. Objective 2. Reduce environmental impacts of catfish aquaculture. Objective 3. Develop management practices to reduce the impacts of environmental off-flavors. Objective 4. Improve harvest efficiency of pond-raised channel catfish. Objective 5. Improve product quality of harvested catfish. Objective 6. Improve spawning efficiency of channel catfish. Objective 7. Improve resource management on catfish farms. 3.Milestones: A. List the milestones that were scheduled to be addressed in FY 2004. How many milestones did you fully or substantially meet in FY 2004, and indicate which ones were not fully or substantially met, briefly explain why not, and your plans to do so. As explained above, milestones were not established for work in FY 2004 in this project. The new project is currently in review through OSQR and the objectives and milestones for that project are listed in Question 3, below. Applicable work for FY 2004 is, therefore, reported for the following specific subobjectives, all of which were accomplished in FY 2004: Objective 1: Increase the reliability, efficiency, and cost-effectiveness of catfish fry production through the use of new and improved technologies. Subobjective 1. Determine the role of natural pond zooplankton populations on catfish fry survival and growth. Subobjective 2. Develop fertilization practices to rapidly stimulate phytoplankton blooms and promote desirable zooplankton taxa. Objective 2. Reduce environmental impacts of catfish aquaculture. Subobjective 1. Characterize effluents from catfish ponds. Subobjective 2. Develop management practices to reduce environmental impacts. Objective 3. Develop management practices to reduce the impacts of environmental off-flavors. Subobjective 1. Evaluate the effectiveness of existing algicides in reducing the incidence of off-flavor. Subobjective 2. Develop new management practices to reduce the incidence of off-flavor. Objective 4. Improve harvest efficiency of pond-raised channel catfish. Subobjective 1. Develop a first-generation power supply for an electrically enhanced seine. Objective 5. Improve product quality of harvested catfish. Subobjective 1. Determine baseline levels of blood and muscle physiological parameters. Objective 6. Improve spawning efficiency of channel catfish. Subobjective 1. Determine if sounds produced during spawning are important to the catfish mating process. Objective 7. Improve resource management on catfish farms. Subobjective 1. Develop a wireless networking system to gather and manage information on catfish farms. B. List the milestones that you expect to address over the next 3 years (FY 2005, 2006, and 2007). What do you expect to accomplish, year by year, over the next 3 years under each milestone? The objectives and milestones for the Project Plan recently submitted for OSQR review are listed below. Objective 1: Develop feeds and feeding practices for optimal nutrition, increased production, and improved water quality of pond-raised catfish. Milestones FY 2005 - Initiate pond feeding trials in a 2 x 4 factorial design using 32% crude protein feeds with 2 fish meal levels (0% and 8% menhaden fish meal) and 4 feed ingredient combinations (soybean meal + corn, soybean meal + corn + wheat middlings, soybean meal + corn + cottonseed meal, soybean meal + corn + cottonseed meal + wheat middlings). FY 2006 - Complete FY 2005 pond feeding trial. Initiate pond feeding trials in a 2 x 4 factorial design using 28% crude protein feeds with 2 fish meal levels (0% and 8% menhaden fish meal) and 4 feed ingredient combinations (soybean meal + corn, soybean meal + corn + wheat middlings, soybean meal + corn + cottonseed meal, soybean meal + corn + cottonseed meal + wheat middlings). FY 2007 - Complete FY 2006 feeding study. Hypothesis 2: Interactions among fish size (fingerlings, stocker-size, foodfish) and feeding schedule (satiation vs. various restricted rations) affect economic performance of catfish farming. Milestones FY 2005 - Initiate long-term pond feeding trial using three feeding regimes:. 1)feeding to apparent satiation once daily;. 2)feeding to apparent satiation once every other day;. 3)feeding once daily to no more than 90 kg/ha. FY 2006 - Harvest marketable fish from study initiated in FY 2005 and restock with fingerlings. FY 2007 - Harvest marketable fish from study initiated in FY 2005 and restock with fingerlings. Objective 2: Increase the reliability, efficiency, and cost-effectiveness of catfish fry production through the use of new and improved technologies. Hypothesis 1: Implementation of new nursery pond management strategies can improve fry growth and survival on a commercial catfish farm. Milestones FY 2005 Initiate studies of "best management practices" for fry nursery ponds on commercial farm. FY 2006 Complete year 1 studies of "best management practices" for fry nursery ponds on commercial farm; evaluate and model results; modify management practices and initiate year 2 of study. FY 2007 Complete year 2 studies of "best management practices" for fry nursery ponds on commercial farm; evaluate and model results; modify management practices and initiate year 3 of study. Hypothesis 2: Increased nitrogen fertilization rates will improve fry growth and survival. Milestones FY 2005 - Initiate studies in replicate fry ponds fertilized with different levels of nitrogen fertilizer (5, 10, 20, 30, or 40 kg/ha N initial application followed by twice weekly applications of half the initial rate) and 2 kg/ha P initial application followed by twice weekly applications 1 kg/ha P. FY 2006 - Harvest fish from FY 2005 study; analyze data; refine fertilization rates, and initiate year 2 studies. FY 2007 - Harvest fish from FY 2006 study; analyze data; recommend optimum fertilization rate to industry. Hypothesis 3: Zooplankton affect growth, survival, and immune response of catfish fry. Milestones FY 2005 - Initiate laboratory studies of the effect of feeding supplemental zooplankton on fry growth, survival, immune response, and survival to disease challenge FY 2006 - Complete data analysis of FY 2005 studies; refine diets and repeat study using basic protocol used in FY 2005 FY 2007 - Complete data analysis of FY 2006 studies; recommend optimum fry feeding strategy to industry Objective 3: Apply engineering approaches to design new or modified live aquatic animal harvesting equipment. Hypothesis: Incorporating an induced electrical field into a seine improves harvest efficiency of pond-raised catfish. Milestones FY 2005 - Complete design, fabrication, and testing of components in vats. FY 2006 - Complete laboratory vat testing; redesign components. FY 2007 - Initiate vat studies on capture efficiency of prototype seine; initiate design and fabrication of pilot-scale seine. Objective 4: Increase the reliability, efficiency, and cost-effectiveness of catfish production through the use of new and improved culture system technologies. Hypothesis 1: Radical changes in the design of ponds, incorporating the concepts of fish confinement and water circulation, can improve catfish production efficiency. Milestones FY 2005 - Initiate construction of sidestream bypass Partitioned Aquaculture System. FY 2006 - Complete construction; initiate performance testing and design optimization. FY 2007 - Initiate comparative fish growth trials Hypothesis 2: Development of an environmental management system for pond aquaculture, consisting of proven or easily implemented technologies, can improve catfish production efficiency, reduce environmental impacts, and conserve water. Milestones FY 2005 - Develop Environmental Management System; initiate year 1 of comparative production trials. FY 2006 - Initiate year 2 of comparative production trials. FY 2007 - Initiate year 2 of comparative production trials. 4.What were the most significant accomplishments this past year? A. Single most significant accomplishment during FY 2004. Objective; Subobjective 2. Develop management practices to reduce environmental impacts. The United States Environmental Protection Agency recently announced the decision to develop nationally applicable discharge standards for aquaculture. In response to this challenge, we evaluated a simple set of best management practices to reduce mass discharge - the product of concentration and volume discharged over time - of potential pollutants from catfish ponds. One of the practices, water-level management, was implemented to reduce effluent volume. The other three practices were implemented to reduce the concentration of substances in effluents. Those practices were. 1)limiting daily feed inputs to 110 kg/ha per day,. 2)using a 28% protein feed, and. 3)maintaining a maximum fish density of 18,500 fish/ha. Pollutant discharge and fish production from EMS ponds are being compared to "traditional" ponds managed without water-level management, without feed limitation, using a 32% protein feed, and with a stocking scheme where 24,700 fish/ha are added each spring. the amount of waste produced within catfish ponds and decrease the volume of water discharged from ponds. After 3 years of study, average mass discharge of total nitrogen, phosphorus, suspended solids, and 5-day biochemical oxygen demand has been reduced by about 70% in ponds managed with the best management practices with no reduction in fish production. Catfish farmers can easily adopt these practices, which will allow catfish farms to be operated with little or no impact on the environment. B. Other significant accomplishments. Objective 1; Subobjective 1. Determine the role of natural pond zooplankton populations on catfish fry survival and growth. The objective of zooplankton research is to help catfish fish farmers adopt management practices that maximize profitability of fry culture through utilization of natural pond productivity and reduced feed costs. Zooplankton are more important to catfish fry culture than previously thought. Catfish fry actively forage on large zooplankton taxa (i.e., copepods and cladocerans); large bodied zooplankton from catfish nursery ponds meet or exceed all nutritional requirements for channel catfish fry (65% protein, 9% fat). Preliminary laboratory studies indicate zooplankton, in conjunction with commercial feed, have a positive effect on fry growth, survival, and general fish health. In several trials, vaccinated fry fed zooplankton performed better when challenged with ESC than vaccinated fry not fed zooplankton and non-vaccinated fry. This research may have major implications regarding management decisions. Ponds should be managed to increase the numbers of large sized zooplankton. Objective 1; Subobjective 2. Develop fertilization practices to rapidly stimulate phytoplankton blooms and promote desirable zooplankton taxa. Increasing densities of desirable zooplankton can be accomplished through pond fertilization practices. To determine if previously recommended fertilization practices are appropriate for the Delta, we evaluated phytoplankton and zooplankton responses organic, inorganic, and a combination of both fertilizer types in newly constructed versus established catfish nursery ponds. We found that increasing nitrogen application rates (20 kg/ha N followed by twice a week at half rate vs. 8 kg/ha N followed by twice a week at half rate) stimulated the phytoplankton bloom more quickly and significantly increased preferred zooplankton densities. Dramatically changing previous pond fertilization practices can increase the densities of important zooplankton and should improve fry growth, survival and health. Objective 2; Subobjective 1. Characterize effluents from catfish ponds. Development of effective waste management plans for pond aquaculture depends on characterization of the water discharged from ponds. We conducted a study to assess quality of pond effluents when ponds are drained and to characterize the nature of the material discharged. When ponds are drained, the initial flush of water discharged consists of pond water and a slurry of sediment that has accumulated over the screen inside the pond, but the effluent clears in 5 to 30 minutes and all water subsequently discharged is simply pond water. Since only a small proportion (1 to 4%) of the total solids discharged during pond draining was contained in the initial flush, it will be uneconomical to design elaborate treatment facilities to remove the material in that small volume of water. Objective 2; Subobjective 2. Develop management practices to reduce environmental impacts. Processes that rely on gravity settling are the most economical method of removing solids from the initial flush of water released when ponds are drained. We measured the settling characteristics of solids in catfish pond effluent and used non-linear equations to calculate design criteria for settling basins. For average pond discharge rates, removal of 95% of solids requires a basin area ranging from 95 to 125 square meters. These data will allow environmental engineers to design effective treatments for catfish pond effluents. It is economically impractical to build new treatment facilities to remove solids from catfish pond effluents; however, existing drainage ditches may act simultaneously to transport water and remove solids. We assessed the capacity of ditches with volunteer vegetation to remove solids and nutrients from catfish pond effluents. At typical pond effluent discharge rates, in excess of 95% of the solids in initial pond draining effluent was removed after the effluent traveled 120 to 220 meters downstream in a 1-meter wide ditch. This was consistent with the results of basin-design modeling and show that it is unnecessary to build elaborate facilities to improve catfish pond effluent quality because considerable improvement in quality occurs as effluent flows down the simple drainage ditches that are common features of most commercial catfish farms. Objective 3; Subobjective 1. Evaluate the effectiveness of existing algicides in reducing the incidence of off-flavor. Farm-raised catfish often develop undesirable "off-flavors" that cost catfish farmers $15 to 75 million per year. We conducted a 3-year study to evaluate the effectiveness of weekly low-dose applications of copper sulfate (0.12 mg Cu/L) on the prevalence of off-flavor in catfish on commercial farms. Levels of the odorous compound, 2-methylisoborneol, and the abundance of the MIB-producing cyanobacterium Oscillatoria perornata were significantly reduced in treated ponds compared to controls at one farm, while numbers of green algae and diatoms increased significantly at both farms. In addition, the overall prevalence of all types of off-flavor was reduced by 50% based upon fish flavor analysis. Copper sulfate treatment reduced potential harvest delays by nearly half and reduced costs associated with off-flavor by 35%. However, the economic benefit of treatment was not statistically significant, although this is likely the result of the limited dataset used for economic analyses rather than ineffectiveness of treatment. Based upon our results, weekly low-dose applications of copper sulfate appear to be beneficial in mitigating musty off-flavor problems in commercially produced catfish. Objective 3; Subobjective 2. Develop new management practices to reduce the incidence of off-flavor. Currently there are only two algicides, copper sulfate and diuron, registered for managing algae-related off-flavors in pond-raised catfish. We cooperated with personnel from the USDA-ARS Natural Products Research Unit, Oxford, Mississippi, to identify and evaluate new algicides for use in managing algae-related off-flavors. One promising compound ¿ a modified anthroquinone ¿ identified in laboratory screening was tested in outdoor mesocosms and found to be selectively algicidal to odor-producing blue-green algae, thereby reducing levels of odorous compounds in water. Objective 4; Subobjective 1. Develop a first-generation power supply for an electrically enhanced seine. We are developing a low power electrical stimulation (LPES) system that can be embedded safely into a conventional seine to improve its harvest efficiency. During 2004, vat studies using market sized channel catfish were conducted using a newly designed, custom built power supply which produced waveforms previously identified as effective in repelling catfish away from electrodes. Both size and weight of the power supply were reduced to about 50% of the weight of the power supply used in most commercial electro-shocking units. The power supply proved to be only moderately effective in repelling the fish away from the electrodes. Fish generally avoided the electrodes. However, the smaller than expected size of the electrical field only keep the fish about a foot away from the electrodes which resulted in fish crossing the electrodes when crowded. The results of these tests will be used to design a second generation power supply for testing. This research is expected to lead to reductions in the cost of harvesting catfish from ponds. Objective 5; Subobjective 1. Determine baseline levels of blood and muscle physiological parameters. Recovery from exhaustive exercise is important because it determines the performance limits of a fish. The potential frequency of maximal performance in fish is set by the time requirements for recovery and restoration of energy stores. Therefore, we conducted a series of swim-tunnel studies to determine the length of time blue and channel catfish need to recover from bouts of exhaustive exercise. No differences were found between blue and channel catfish blood lactate, glucose, or cortisol concentrations. However, pre-exercise blood physiology levels were significantly lower than levels determined at the time of fatigue. All fish in these studies recovered from exhaustive exercise within four hours. The results of these studies may be useful to researchers when future studies on harvesting techniques are conducted. Objective 6; Subobjective 1. Determine if sounds produced during spawning are important to the catfish mating process. Channel catfish spawning success is highly variable and is considered an important problem in catfish farming because dependable reproduction is essential to the development of any food-animal industry. For the last four years, we have cooperated with scientists at the University of Mississippi National Center for Physical Acoustics to monitor breeding populations of channel catfish during the spawning season to determine if they produce sounds during breeding and whether these sounds are important to their mating success during pre-spawning, spawning, and post-spawning activities. A number of low frequency sounds have been identified and are being evaluated to determine their characteristics and importance. This research is expected to lead to improvements in brood pond management. Objective 7; Subobjective 1. Develop a wireless networking system to gather and manage information on catfish farms. The size and complexity of modern catfish farms make it difficult to track and manage people, equipment and data in real time. Mississippi State University scientists at the National Warmwater Aquaculture Center in Stoneville, Mississippi, and in the Department of Agricultural and Biological Engineering are developing a wireless networking infrastructure with specialized hardware and software products that enables custom-designed and ¿traditional¿ instruments to become networked and web-enabled distribution devices. During the past year, a prototype I wireless network with the embedded software for data handling and analysis was installed at the Delta Western Research Center in Indianola, Mississippi. A satellite link was installed to allow the system to be accessed and controlled remotely. The system is being used to test the functionality of the data handling, storage, and analysis software and to test the reliability of the system. Once this phase of testing is complete, sensors will be added to mechanical and environmental instruments and monitored automatically as needed. When fully developed, the system will reduce the cost and greatly simplify the management of electronic information on farms. c. Significant activities that support special target populations. Off-flavor problems in commercial catfish culture reduce profits and methods developed to control off-flavor producing algae in ponds will benefit operators of small farms. The USDA Census of Aquaculture conducted in 2000 classified 84% of catfish farms as small businesses, with annual sales of less than $500,000. Of the 1,370 catfish farms in the United States, 38% (515) reported annual revenues of less than $25,000. Off-flavors disproportionately affect small farms because they are more susceptible to economic impacts related to interruption of cash flows and there is less probability of having acceptable fish to sell from at least one pond on the farm when only a few ponds are available. D. Progress report. None. 5.Describe the major accomplishments over the life of the project, including their predicted or actual impact. Previously, it was not clear which zooplankton catfish fry consumed, or if fry consumed zooplankton at all. Research at the National Warmwater Aquaculture Center in Stoneville, Mississippi determined that catfish fry do consume zooplankton and have a preference for the larger zooplankton taxa. These larger zooplankton are highly nutritious for catfish fry, providing all known nutritional requirements. Changing fertilization regimes to increased nitrogen application rather than phosphorus can develop a phytoplankton bloom more quickly and significantly increase the densities of desired zooplankton. Farmers have already adopted these practices as part of routine pond management. Research at the National Warmwater Aquaculture Center in Stoneville, Mississippi, also determined the waveform and electrical array that was most effective in capturing catfish, demonstrating that electricity could be used effectively to improve harvest efficiencies. This work will be the basis for future research that may lead to significantly increased fish harvest efficiency. Effective control measures for algae-related off-flavors have also been developed with very high benefit-cost ratios. Residues resulting from use of these algicides have been found to be far below regulatory limits. These safe and effective off-flavor control measures are now routinely used in the farm-raised catfish industry. Effluent management practices have been developed and are part of EPA and industry-endorsed practices to reduce environmental impacts of catfish farming. 6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Off-flavor treatment regimens have been described in producer's trade journals and at several Extension workshops. Technologies have also been described in a regional publication published by the Southern Regional Aquaculture Center. That technology has, therefore, been transferred to the appropriate user group, and is currently in widespread use. Effluent management practices have been described in a producer's trade journal, at scientific meetings, in various workshops, in book chapters and in documents submitted to the U.S Environmental Protection Agency. Results of studies of zooplankton selective by channel catfish fry were presented at scientific meetings and results have been disseminated to catfish farmers through verbal communications and have been submitted to an extension publication and a scientific journal. Studies of pond successional changes have been published in a scientific journal, an extension publication, and presented at scientific and extension meetings. Swim-study results have been presented at Extensions workshops and published in an Extension newsletter. The electrical seine studies have been presented at an Extension work shops and at a scientific meeting; one article has been published and another article submitted to a scientific journal. The sound studies have been presented at an Extension workshop and a portion of the work presented at a scientific meeting. The web-based wireless network system has been presented at scientific meetings. 7.List your most important publications in the popular press and presentations to organizations and articles written about your work. Hargreaves, J. and Tucker, C. 2004. Characterization and discharge of solids from semi-intensive aquaculture ponds. Book of Abstracts - Aquaculture 2004, March 1-5, Honolulu, Hawaii. Meepagala, K.M., Sturtz, G., Mischke, C.C., Joshi, R.C., Duke, S.O. 2004. Natural molluscicides aginst ram¿s horn and golden apple snails. 227th National Meeting & Exposition of the American Chemical Society, March 28-April 1, 2004, Anaheim, California. Minchew, C.D. and RV. Beecham. Swim-tunnel respirometer: Its usefulness as a tool to study catfish health and physiology. NWAC News. July 2004. Beecham, R.V., C.D. Minchew, and G.R. Parsons. Non-horizontal swimming performance of channel catfish fingerlings. Mississippi Chapter American Fisheries Society Meeting. February 11-13, 2004, Jackson, Mississippi. Minchew, C.D. and R.V. Beecham. Catfish metabolism. The Catfish Journal. December 2003. Mischke, C.C. 2003. Bioaugmentation-biotics in catfish ponds. NWAC Fall Seminar program, November 6, 2003. Mischke, C.C., Wise, D.J., Zimba, P.V. 2003. Catfish fry pond fertilization. NWAC Catfish Hatchery Management Workshop, March 27, 2003. Mischke, C.C., Wise, D.J., Li, M.H., Zimba, P.V. 2003. Zooplankton and catfish fry culture. NWAC Catfish Hatchery Management Workshop, March 27, 2003. Mischke, C.C. 2004. Pond preparation and water quality for freshwater prawn culture. USFPSGA Newsletter 3(1):2. Mischke, C.C., Zimba, P.V. 2004. Optimizing fry pond fertilization. The Catfish Journal 18(8):10-11, 22. Mischke, C.C., Zimba, P.V. 2003. Optimizing fry pond fertilization. NWAC News 6(1):4, 10. Tucker, C. S. 2003. Solar power for catfish pond aeration. The Catfish Journal XVII(7):24. Tucker, C. S. and Harris, S. 2003. Research on catfish harvesting and grading. NWAC News 6(1):5. Tucker, C. S. and Kingsbury, S. K. 2003. Uses and misuses of sodium bicarbonate. NWAC News 6(1)1-3. Tucker, C. S. and Harris, S. 2004. Research on fish diseases. NWAC News 7(1):9. Tucker, C. S., Hargreaves, J., Rutherford, D. and Kingsbury, S. 2004. An environmental management system for catfish pond effluents. NWAC News 7(1):4. Tucker, C. S., Hargreaves, J., Rutherford, D. and Kingsbury, S. 2004. An environmental management system for catfish pond effluents. Book of Abstracts - Aquaculture 2004, March 1-5, Honolulu, Hawaii. Wise, D.J., Terhune, J.S., Mischke, C.C. 2003. Evaluation of AQUAVAC-ESC vaccinated fish using single and continuous dose challenge models. NWAC Catfish Hatchery Management Workshop, March 27, 2003. Zimba, P.V., Camus, A., Wise, D.J., Mischke, C.C., Triemer, R., Moeller, P. 2004. Euglena sanguinea-associated mass mortalities in cultured striped bass and channel catfish. Combined meeting of the 9th biennial meeting of the Fish diagnostician's workshop/55th annual meeting of the animal disease research workers in southern states/19th annual meeting of the southern conference on animal parasites/6th annual meeting of the southern conference of researchers in aquatic diseases. February 8-10, Isle of Capri Hotel, Biloxi Mississippi. Hargreaves, J. A. and Tucker, C. S. 2004. Industry development. Pages 1-14 in C. S. Tucker and J. A. Hargreaves (editors): Biology and Culture of Channel Catfish. Elsevier, Amsterdam, The Netherlands. Meepagala, K.M., Sturtz, G., Mischke, C.C., Wise, D., Duke, S.O. 2004. Molluscicidal activity of vulgarone B against ram's horn snail (Planorbella trivolvis). Pest Management Science 60:479-482. Mischke, C.C. Zimba, P.V. 2004. Plankton community responses in earthen channel catfish nursery ponds under various fertilization regimes. Aquaculture 233:219-235. Mischke, C.C. 2003. Evaluation of two bio-stimulants for improving water quality in channel catfish, Ictalurus punctatus, production ponds. Journal of Applied Aquaculture 14(½):163-169. Schrader, K. K., Rimando, A. M., Tucker, C.S., Glinski, J., Cutler, S. J. and Cutler, H. G. 2004. Evaluation of the natural product SeaKleen for controlling the musty-odor producing cyanobacterium Oscillatoria perornata in catfish ponds. North American Journal of Aquaculture. 66:20-28. Steeby, J.A., Hargreaves, J. A., Tucker, C. S. and Kingsbury, S. K. 2004. Accumulation, organic carbon, and dry matter concentration of sediment in commercial channel catfish ponds. Aquacultural Engineering 30:115-126. Tucker, C. S. 2003. Best management practices for pond aquaculture. Pages 93-109 in R. C. Summerfelt (editor). Aquaculture Effluents: Overview of EPA Guidelines and Standards and BMPs for Ponds, Raceways, and Recycle Systems. North Central regional Aquaculture Center, Iowa State University, Ames, Iowa. Tucker, C. S. 2003. Channel catfish. Pages 346-363 in J. S. Lucas and P. C. Southgate (editors), Aquaculture: Farming Aquatic Animals and Plants. Blackwell Publishing, Ltd., Oxford, UK. Tucker, C. S. and Hargeaves, J. A. 2003. Copper sulfate to manage cyanobacterial off-flavors in pond-raised channel catfish. Pages 133-146 in A. M. Rimando and K. K. Schrader (editors), Off-Flavors in Aquaculture. American Chemical Society, Washington, D.C. Tucker, C. S. and Hargreaves, J. A. 2003. Management of effluents from channel catfish (Ictalurus punctatus) embankment ponds in the southeastern United States. Aquaculture 266:5-21. Tucker, C. S. and Hargreaves, J. A. 2004. Water quality management. Pages 215-278 in C. S. Tucker and J. A. Hargreaves (editors): Biology and Culture of Channel Catfish. Elsevier, Amsterdam, The Netherlands. Tucker, C. S., Avery, J. and Heikes, D. 2004. Culture methods. Pages 166-195 in C. S. Tucker and J. A. Hargreaves (editors): Biology and Culture of Channel Catfish. Elsevier, Amsterdam, The Netherlands.