Critical to the growth of the shrimp farming industry is optimization of the technology for induced maturation, Postlarvae (PL) production, nursery, grow-out, effluent water quality control, and disease diagnosis and prevention. <P>
The objective of the proposed research is to develop basic knowledge necessary to support a strong and viable shrimp farming industry in Texas. Specifically, the following objectives will be emphasized over the next five years: <OL> <LI> To investigate nutritional requirements for: (a) Production of native PL (Litopenaeus setiferus), and one exotic species (L. vannamei) in captivity; (b) Rearing PL of native species to bait-size in tanks, raceways, and ponds; c) Rearing PL and juveniles of exotic and native species to food-size in ponds and greenhouse-enclosed raceways with no water exchange; <LI> To further develop technology for intensive outdoor pond systems with limited discharge; <LI> To develop technology for indoor super-intensive closed recirculating raceway systems;<LI> To continue the development of nursery raceway technology for rearing of PL to juvenile stages in order to increase farms' profitability; <LI> To develop technology for production and overwintering of broodstock; <LI> To develop cost-effective preventive and treatment methods to reduce potential negative impact from shrimp farms' effluent water on receiving waters. This will include: (a) Characterization of effluent water from coastal shrimp farms; (b) Evaluation of the beneficial effect of implementing preventive methods to improve effluent water quality, such as: (i) Increasing pond aeration rates; (ii) Reducing and/or eliminating water exchange; (iii) Using formulated feeds with low/high protein and low phosphate levels; (iv) Using fish meal replacement in shrimp diet formulation; and (v) Using feed management that improves FCR's; (c) Evaluation of the beneficial effect of implementing treatment methods to improve effluent water quality including the potential use of: (i) Settling basins; (ii) Bivalves; (iii) Seaweeds; (iv) Bacterial-supplements and/or enzymes (v) Halophytes. <LI> To develop cost-effective biosecure preventive and treatment management strategies to reduce the risk of spreading viral diseases and crop losses due to disease outbreaks. Such strategies include the use of: (a) Adequate animal husbandry protocols; (b) Disinfection of culture water; (c) Elimination/reduction of water exchange; (d) Medicated feeds; and (e) Genetically improved specific-pathogen-free (SPF) broodstock.<LI> To evaluate the feasibility of using the halophyte Salicornia for remediation of nutrient rich shrimp effluent water and for the production of biodiesel and other high value byproducts. <LI>To produce microalgae in outdoor raceways using flue gas CO2 from the adjacent Barney Davis Power Plant. <LI> Transfer of new technologies to shrimp producers in Texas.
NON-TECHNICAL SUMMARY: Shrimp is the #1 selling seafood product in the US. Out of approximately 630K tons of shrimp consumed in the US in 2007, about 90% was imported, accounting for a $3.9 billion trade deficit. With wild fisheries having reached their maximum sustainable yields, increases in shrimp consumption will depend on growth of the shrimp aquaculture industry. Of the total shrimp consumed in the US, the portion supplied by domestic fisheries account only for about 10%. This is primarily due to the low cost of imported shrimp, and the rising cost of fuel. Domestic shrimp farms are required by law to show environmentally sound production practices, including the use of disease-free seedstock, biosecure protocols, low-impact feeds, & water reuse. Concerns about food safety issues, healthier eating habits, & increasing transportation costs can make domestically cultured shrimp a viable US product. However, traditional pond culture methods practiced in the US cannot compete economically against the flood of inexpensive shrimp products (both farm-raised & wild-caught) imported from Asia & Latin America. What is required is the development & transfer of advanced & innovative technologies to leverage US industry gains, enhance competitiveness, & improve profitability, with an emphasis on specialty niche markets that can only be served by domestic producers. Results from a 2009 study at our facility showed that juveniles (0.99 g) of the Pacific White Shrimp, Litopenaeus vannamei, can be raised at high density (450/m3) & reach marketable size of 22 g in 108 d with high survival (>94%), good growth (>1.37 g/wk) & high yield (> 9.53 kg/m3) under no water exchange. Shrimp production in this type of super-intensive system takes place in a controlled environment, so food security is greatly enhanced. These systems can provide a year-round supply of high-priced live and/or fresh never-frozen shrimp that will set it apart from imported frozen product. In addition to being the leader in food-size shrimp production, TX plays a significant role in the development of the live bait shrimp industry in the country. However, increased regulations on wild live bait shrimp catches coupled with seasonal shortage & recent discoveries of native populations infected with virulent viruses in SC and TX waters suggest that preventive measures are needed to avoid further environmental damage. Development of viral-pathogen-free farm-raised live bait shrimp industry in TX can be a profitable business that satisfies market demand while minimizing the risk of spreading viral diseases to wild populations. To help the growth of the US shrimp farming, research at the facility will focus on different aspects which can make this industry more competitive. Research will include development of more competitive, sustainable & cost-effective shrimp production methods. Beside the planned research on the above listed areas, research will also be conducted on growing the halophyte Salicornia for mariculture effluent water remediation & for production of protein & oil. Finally work will also focus on growing microalgae for the production of oil & byproducts using CO2 flue gas form power plant.
APPROACH: All studies will be conducted at the Texas AgriLife Research Mariculture Lab at Flour Bluff, Corpus Christi. The maturation/reproduction experiments with native species will be conducted in a closed-recirculating three-tank system. Larval nutritional studies will be conducted in a small experimental system with 77 Imhoff cones. Studies on the nutritional requirements of shrimp in the nursery and grow-out phases and the development of biosecure and sustainable shrimp production practices will be conducted in eight greenhouse-enclosed raceways (two of 100 m3 and six of 40 m3), four 2,500 m3 outdoor membrane-lined ponds, twenty-four 7.6 m3 outdoor tanks under a shade, and eighty-four 0.65 m3 tank-systems under roofing. The studies on the halophyte will be conducted in an experimental constructed wetland and in a small greenhouse. The studies on the production of microalgae for biofuel and byproducts will be conducted in twelve 3 m2 outdoor tanks and in different size outdoor raceways. Algae to be produced at the lab will be concentrated and shipped to other researchers from the Texas A&M System to identify the most cost-effective lipid extraction methods. An on-site laboratory will serve to conduct water quality analyses including ammonia-N, nitrite-N, nitrate-N, cBOD5, TSS, VSS, COD, settleable solids, reactive phosphorus, and TKN.