36 DECEMBER 2017 • WORLD AQUACULTURE • WWW.WAS.ORG the need to buy or create pellets is referred to as “Aquamimicry fermented soybeans” (AFSY). Despite being contrary to traditional farming practices, AFSY has been successful in the extensive and semiintensive farming of black tiger shrimp and whiteleg shrimp in some parts of Thailand, Vietnam, Ecuador and India. This brief article will describe the overall methodology of pellet-free farming by using AFSY as a potential means to improve the cost-effectiveness and sustainability of shrimp aquaculture. Application of AFSY does not require harsh chemicals or antibiotics because diseases are minimized and water quality improved. Efforts are underway to disseminate this knowledge to farmers throughout the world and to share their experiences, opinions and advice with others (Figs. 1 and 2). Study Methods This method relies on implementing the Aquamimicry concept within ponds by adding FRB to stimulate the natural production of zooplankton (particularly copepods) prior to stocking shrimp. To create FRB, rice bran is ground to a fine powder, added to water at a 1:1 ratio and then Bacillus probiotics or hydrolytic enzymes are added with aeration. After 24 hours, an initial application of the mixture is made to ponds at 50-100 ppm. Copepods will bloom within two weeks, depending on water source, temperature and previous pond management, but can be as early as two days. Periodic applications of probiotics to pond water and dragging a chain around the pond bottom should also be done. It is not necessary to have a split-pond design as required for Aquamimicry. More details on this protocol Shrimp farming can be a highly lucrative business around the world, but has increasingly been characterized by intensification, with greater inputs of feed. Intensification has increased the risk of disease outbreaks and the proportion of operating costs represented by feeds can be as much as 60 percent. Various strategies have been investigated to address these issues, such as using functional feeds designed to improve the productivity and health of shrimp by additions of supplements. Moreover, researchers are continually evaluating appropriate replacements for more-expensive marine ingredients (Gatlin et al. 2007). One of the potential constraints in shrimp feeds, however, is the requirement for expensive cholesterol and pigments. Additional supplements such as probiotics, prebiotics, extracts and organic acids to create functional feeds further increases feed cost. Consequently, the purchase of commercial aquafeeds may be out of reach for many small-scale farmers around the world. Alternatively, farmers can make pellets on site with locally available ingredients and/or using trash fish (Gonzalez and Allan 2007). There are several drawbacks to this practice, such as inefficient use of feeds, leading to water quality deterioration, variable ingredient quality and the potential introduction of pathogens (Kim et al. 2007). In this situation, a potentially better approach might be to combine the “Aquamimicry” concept that relies on the use of fermented rice bran (FRB) to stimulate natural zooplankton (Romano 2017) with the sole provision of fermented soybeans (FSY) as feed for shrimp. This combination that completely replaces Vegetarian Shrimp: Pellet-free Shrimp Farming Nicholas Romano and Vikas Kumar FIGURE 1. Aquamimicry Workshop in Thailand, 2017. FIGURE 2. Expert on Aquamimicry and pellet-free feeding expert, Mr. Veerasun Prayotamornkul, presenting production results on this protocol in Hua Hin, Thailand, 2017.
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