WWW.WAS.ORG • WORLD AQUACULTURE • MARCH 2017 53 reflected in the production profit. Better growth can be achieved with high-protein feeds (35 percent) and when using functional feeds that promote shrimp health. In Table 3 two scenarios are compared: use of two different feeds (brand A is 10 percent more expensive than brand B) and the expected production obtained at the end of the culture period with both feeds. The same survival (70 percent), harvest weight (20 g) and FCR (1.5) were assumed to observe the positive impact of shrimp growth on efficiency of the production model. A fixed cost (US$20/ha per d) that includes all production costs except the cost of feed of is assumed. The fixed cost for semi-intensive production models can fluctuate between 40-60 percent of total costs. The exercise shows that a production model oriented to a higher weekly growth rate (>1.4 g/wk) allows the reduction of the culture period by 20 d, representing an increase in the PI/ha per d of more than 20 percent. This greater profitability can be obtained with brand A, even though it has a higher price than brand B. Assessment of the PI/ha per d allows construction of simulations to define the productive model better suited to the conditions on the shrimp farm in terms of seasonality, technology, management and financial capability. In Table 4 two scenarios are compared: use of two different feeds (brand A is 10 percent more expensive than brand B) and the expected (CONTINUED ON PAGE 54) TABLE 1. Evolution of productivity of the shrimp industry in Ecuador. Source: Quispe, M. 2013. VI Simposio Nicovita. Year Stocking density Biomass (lb/ha) Survival (%) FCR (shrimp/m2) 1994 7 1294 70 2.6 1997 8 1478 60 2.5 2000 8 686 30 2.4 2003 8 1144 50 2.2 2006 10 1815 55 2.0 2009 10 1980 60 1.7 2012 10 2112 60 1.6 2015 11 2468 60 1.6 TABLE 2. Evolution of production techniques in Ecuador by decade. 1990-1999 2000-2009 2010-2016 Biomass of production (lb/ha) 1500 2000 3000 Larva origin Wild Hatchery Hatchery Hatcheries Beginning Consolidated Genetic programs Feeding method Broadcast/Tables Broadcast/Tables Total feed on trays Total feed on trays Total feed on trays Visualization Samples on feed trays Automatic feeding Nutrition Low nutritional profile Better nutritional profile High nutritional profile Functional diets Infrastructure Shallow ponds Shallow ponds Deeper ponds Water exchange (%) <3% weekly <5% weekly >10% weekly Technology use Incipient use of raceways Use of raceways Use of raceways Use of nurseries Incipient use of aeration Use of aeration Use of efficient aeration Bioremediation Bioremediation Recirculation Recirculation Biosecurity Analysis and aquatic sanitation laboratory Production indicators Harvest weight Harvest weight Productive Economic Index (PI/ha per d) Production biomass Production biomass Productive Efficiency Index (PEI) Profit/ha
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