26 DECEMBER 2013 • WORLD AQUACULTURE • WWW.WAS.ORG more than sinking feed. The production rate of grower feed is 1-2 t/h greater than that of starter feed, while energy consumption in machine operation and protein inclusion costs are greater for starter feed than for grower feeds. The price of aquafeed increased 20-25 percent between 2011 and 2012 from increases in the price of most major raw materials. The main raw materials used for aquafeed production and their inclusion rates are rice bran (20-50 percent), maize (520 percent), soybean meal (10-20 percent), mustard oil cake (10-25 percent), fishmeal (5-15 percent) and meat and bone meal (10-20 percent). Three types of rice bran are used: de-oiled rice bran (DORB), grade A rice bran (85-90 percent bran), and grade B rice bran (40-50 percent husk and 60-50 percent bran). The protein content of DORB (15-17 percent) is greater than that of grade A rice bran (10-13 percent). Rice bran is produced mainly locally. Maize originates from local (75-80 percent) and imported (20-25 percent) sources. Soybean is mainly imported from South America, although around 150,000 t was grown in Bangladesh in 2012. Soybeans are used primarily for the extraction of oil for human use, and the meal or cake byproduct is used in feeds. There are two solvent extraction mills in Bangladesh, providing 35-40 percent of soybean meal/cake supply, with the remaining 60-65 percent imported from India. Incorporation rates of soybean meal/cake are less in sinking (10-20 percent) than floating (20-30 percent) aquafeeds. Meat and bone meal is a source of cheap protein (48-52 percent crude protein) and is imported, particularly from Australia and Paraguay. Inclusion rates for all major protein sources — soybean meal, meat and bone meal, mustard oil cake and rapeseed meal — vary according to their respective prices, nutritional value and availability. These products are available in different quality grades. Local fishmeal is manufactured from a variety of trash fish, crabs and other aquatic animals. Thus, the nutritional composition is variable. Large quantities of salt are added during drying to aid long term preservation, increasing the weight of dried fish by up to 20 percent. Fishmeal is sometimes intentionally adulterated with salt to increase product weight by up to 35-40 percent. The crude protein content of meal derived from this dried fish varies from 35 to 45 percent. There is a domestic source of better-quality fishmeal (44-52 percent crude protein), made from ‘chewa’ Pseudapocryptes elongates produced in southern Bangladesh in Kuakata and the islands of Hatia and Bohala, but supply is insufficient to meet the demand of the aquafeed sector (Fig. 7). However, almost 80-85 percent of fishmeal used in the production of aquafeeds originates from local sources. Alternative (conventional and unconventional) raw materials are used when the price of regular raw materials rises but feed prices cannot be increased further because of market competitiveness. Alternative raw materials used include cassava, millet, pulse meal, broken rice, shrimp shell, small dried crab, dried fish offal from processing plants, canola meal, blood meal, sorghum meal, copra meal, wheat bran, groundnut meal, cottonseed meal, guar meal, feather meal and poultry offal. Use of lower-quality alternative or unconventional raw materials often occurs as a result of shortages or price hikes of standard ingredients. Wide variation in the crude protein content and amino acid profiles of meat and bone meal and fishmeal also affects the performance of feed. Mycotoxin problems arise from May to August from high humidity, procurement of raw materials with high moisture content, such as rice bran and maize, and poor storage. Variations in the price of aquafeed ingredients are linked to commodity price fluctuations in international markets, changing import policies and foreign relations with exporting countries. Imported raw materials contribute more than 50 percent of the total cost of aquafeed production. Raw materials are generally supplied to feed mills by a number of distributors, but large feed mills open letters of credit that allow direct import of ingredients, thereby reducing costs. Feed mills also procure domestically produced ingredients such as rice bran and maize through their national network of feed dealers and sales representatives during the postharvest period when prices are lowest. Service Providers to Feed Mills and Farmers More than ten multinational feed additive companies currently operate in Bangladesh. Five human medicine companies manufacture customized vitamin premixes for local feed companies, although the raw materials are imported. Some feed companies and traders pay for use of these processing facilities to produce their own premixes. About half (10-12) of the commercial feed companies have laboratory facilities to conduct proximate analysis, among which 2-3 have near infrared spectroscopy (NIRS) technology for rapid determination of proximate analysis. A small number of private service providers also offer proximate analysis, as do some government organizations, which support these facilities at lower charge. Analysis of mycotoxins, amino acid profiles and antibiotic testing are not available to feed mill operators. FIGURE 7. Dried ‘chewa’ fish – a local source of high-quality fishmeal.
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