WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2015 15 independent entity. This has ensured quality, compliance and safety of aquatic feeds. All shrimp and tilapia are raised in northeast Brazil with industrially compounded aquafeeds produced locally (Fig. 9). Today there are seven feed companies producing shrimp feeds and more than a dozen involved with tilapia feed manufacturing. Due to the large geographical distances in the country and high freight costs, most feed companies have made investments in manufacturing facilities in northeast Brazil to offer more affordable prices and timely deliveries. At the shrimp farm level, feed continues to be delivered exclusively in feeding trays or by manual broadcasting. Although some farms have invested in mechanical blowers and automatic feeders, feeding exclusively in feeding trays remains the most common feeding method (Fig. 10). In tilapia farms, to facilitate daily management, cage farms adopt walkways made from wood, attached to empty barrels, plastic containers or Styrofoam floats. This has allowed multiple daily feedings during grow-out, reducing FCR and improving fish growth (Fig. 11). Production Scale and Markets Operational scale and the species chosen for farming has a significant impact on the way they are traded in the market (Table 1). Some aquatic species are only known and appreciated in specific markets in Brazil. Others, including tilapia and marine shrimp, are commodities, widely accepted in the major capitals of Brazil, including Rio de Janeiro, São Paulo, Brasilia, Belo Horizonte, Salvador, Recife, Fortaleza and Belem. Several shrimp operations in northeast Brazil were designed to produce large quantities of shrimp required to meet long-term sales contracts in the international market, mainly the US and TABLE 1. Production characteristics of shrimp and tilapia farms in northeast Brazil, including scale of production. Characteristics Marine shrimp Tilapia Environment Coastal or inland, brackish water or marine Inland, freshwater Rearing system Earthen pond, semi-intensive Floating cages, intensive Yields 0.8 - 4 t/ha/crop 60-100 kg/m3/crop Crops per year > 3 2 FCR* 1.0-1.5 1.5-1.8 Operation Size Small1 < 50 t/year < 120 t/year Medium2 Up to 250 t/year Up to 360 t/year Large3 > 500 t/year > 720 t/year *Feed conversion ratio 1 Equivalent to less than 10 ha of earthen ponds or less than 600 m3 of floating cages. 2 Equivalent to 50 ha of earthen ponds or 1,800 m3 of floating cages. 3 More than 100 ha of earthen ponds or 3,600 m3 of floating cages. FIGURE 10. Delivery of feeds exclusively in feeding trays remains the most common feeding method on shrimp farms (A), although some farmers have been trying mechanical feeding (B). Photos: Alberto Nunes. A. B. (CONTINUED ON PAGE 16)
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