Recent Advances in Freshwater Prawn Culture in the U.S. OVERVIEW

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1 Recent Advances in Freshwater Prawn Culture in the U.S. OVERVIEW Dr. Benedict (Ben) C. Posadas Assistant Research Professor of Economics Extension Center 1 Use of substrates Higher stocking densities Phase feeding Use of graded juveniles Pond design and construction Pond preparation and management Harvesting and processing Marketing Extension Center 2

2 FWP Research and Extension Effects of Higher Stocking Densities on Harvest Size and Yield at KSU-ARC Aquaculture Research Center, Kentucky State University (KSU-ARC) National Warmwater Aquaculture Center, Mississippi State University (MSU-NWAC) Coastal Research and Extension Center, Mississippi State University (MSU-CREC) Harvest size (g) ,000 24,000 32,000 1,800 1,600 1,400 1,200 1, Prawn yield (lbs/acre) University of Tennessee Extension Service (UTES) Extension Center 3 Stocking density (#/acre) Avg wt Lbs/acre Extension Center 4

3 Artificial Substrate Experiments at MSU and KSU Effects of Added Substrate on Yield and Harvest Size at KSU-ARC (1998) 1, , Yield 1,700 1,600 1,500 1,400 1,460 1,658 1, Gram 1, W/o substrate 40% added 80% added Yield Final wt Extension Center 5 Extension Center 6

4 Effects of Substrate Orientation on Yield and Harvest Size at KSU-ARC (1999) Effects of Added Substrate on Yield and Harvest Size at KSU-ARC (1999) ,453 2,453 Horizontal Vertical 2,500 2,480 2,460 2,440 2,420 2,400 Yield (kg/ha) Yield (kg/ha) 3,000 2,800 2,600 2,400 2,200 2,000 2,653 2,453 2,140 0%-Control 50%-Vert 100%-Vert Yield (kg/ha) Yield (kg/ha) Extension Center 7 Extension Center 8

5 Phase Feeding Experiments at KSU-ARC (2001) Feed Experiments at MSU-CAU (2001) Phase feeding (Control)- Distillers grain for the first four weeks, a 32% protein prawn diet for weeks 5-12, and the 40% protein penaeid diet for weeks The 32% protein prawn diet throughout the production season Kg per hectare Market-size yield (>30g) 1,062 Phase % Prawn Extension Center 9 Channel Catfish Feed 1,800 pelletized 1,600 sinking 1,400 32% protein Shrimp Feed 1,200 pelletized 1,000 sinking 35% protein 800 1,126 Pounds per acre (heads-on) CCF (lb) 1,350 SF (lb) Extension Center 10

6 Graded Juveniles Experiments at MSU and KSU Use of Graded Juveniles in Experiments at KSU-ARC (2000) Price ranges: Post larva (0.01 g) $25-$40 per 1, day juveniles (0.08 g) $45-65 per 1, day juveniles (0.25 g) $60-$75 per 1,000 Air freight for PL s only: At cost + $5 per 1,000 Grading and delivery costs of juveniles ,630 2,276 Graded Ungraded Yield Harvest weight g) 2,700 2,600 2,500 2,400 2,300 2,200 2,100 2,000 Yield Extension Center 11 Extension Center 12

7 Design and Construction of FWP Ponds (MS & KY) Experimental FWP Pond Preparation at MSU-CAU (2001) Experimental ponds at MSU & KSU 0.10, 0.25 water acre Commercial ponds 1 water acre ponds in KY 2, 3 water acres ponds in MS 5, 9 water acres catfish ponds in MS Adequately sloped, 4- inch per 100 ft inch drain pipe & slightly deepened area Catch basins or harvest sumps Drained ponds in Oct Checked soil ph and applied lime in Feb at 2,400 kg/ha Flooded ponds and applied rotenone in May 2001 at 900 ml/pond Installed 1 HP electric aerator in each pond Stocked ponds in June 2001 Extension Center 13 Extension Center 14

8 Experimental FWP Pond Management at MSU-CAU (2001) FWP Harvesting and Processing at MSU-CAU (2001) Pond aeration running all the time Pond DO s and water temperature were checked daily Emergency aeration was added to ponds with critical DO level Nitrite, salinity and ph were checked biweekly Drained ponds, screened drain pipes and pumps Picked up prawns, harvest sumps Prawns were washed, weighed in baskets Prawns loaded into totes with crushed ice Prawns delivered to processing plant Extension Center 15 Extension Center 16

9 FWP Marketing CONSTRAINTS FACING THE PWP INDUSTRY IN THE USA Selling Live FWP Cost of production Cost of harvesting Cost of live-hauling or shipping Hauling or shipping risks Marketing permit Limited market information Niche versus wholesale commodity markets Selling Fresh or Frozen FWP Cost of production Cost of harvesting Costs of chilling or processing, packing and shipping Price risks Limited market information Extension Center 17 Lack of local nurseries Less than half a dozen nurseries nationwide High price for nursed juveniles Stress during transport to distant sites Need for on- site nursery facilities Low survival in grow-out Exp- com grow- out yield gap Relatively low production Insufficient processing, transporting & marketing infrastructure Except in traditional shrimping areas High transport mortality of live FWP Extension Center 18