WWW.WAS.ORG • WORLD AQUACULTURE • MARCH 2017 57 important step in the prevention of entry of diseases to the farm (Fig. 4). The third pillar implemented religiously is the practice of stringent feed management. Unlike feeding fish, where floating pellets are used, shrimp feed sinks and any uneaten feed cannot be seen. It takes immense skill to master the dispensation of the exact amount of feed to a pond of shrimp. Too little feed will reduce growth and health but too much feed will result in a high organic load in the pond. Uneaten feed and excessive excreta produced from excessive feeding will result in the accumulation of organic matter in the pond, producing harmful gases such as ammonia and hydrogen sulphide that deteriorate water quality and supplying the substrate for the growth of pathogenic bacteria and harmful algae (Fig. 5). Thus, it is imperative that the shrimp farmer is able to dispense just the sufficient amount of feed to the intensive shrimp pond by meticulous monitoring of feed trays (Fig. 6). Feed trays are very useful in fine-tuning daily feed distribution and responding to daily changes in weather and water quality. Through experience, many farmers invariably reduce the amount fed immediately when pond water quality begins deteriorating or when diseases are first discovered to have started to infected the shrimp. This is evident in the cases of AHPND (or EMS, Early Mortality Syndrome), IMNV (Infectious Myonecrosis Virus), Vibrio bacterial infections and WFD (White Feces Disease). In the majority of cases this measure is highly effective. The momentary reduction of feed serves to pause organic matter loading to the pond ecosystem, allowing the shrimp and fish to consume edible organic matter remaining in the pond, and allowing the beneficial bacteria to catch up purifying the ecosystem and in the process improving water quality. The Gold Coin R&D farm is the pioneer in the concept of fasting in Lampung. The idea of fasting initially was found to be strange but today it is widely practiced in many successful shrimp farms and occasional fasting is highly remedial. Although production results were mediocre (Fig. 7), it was possible to produce shrimp profitably under challenging environmental conditions (Figs. 8 and 9), testifying that the principles of the three pillars are practical and functional. Notes Yong Thong Poh, Assistant Director (Nutrition and Technical Services), Gold Coin Aquaculture Group, Lampung, Indonesia. yt.poh@goldcoin-group.com and poyoto2002@yahoo.com References Taw, N. 2012. Sustainable Shrimp Farming: Biosecurity and Biofloc Technology. XIV Congreso Ecuatoriano de Acuicultura & Aquexpo, Ecuador. World Aquaculture Society. Poh, Y.T. 2015. Experience and Vision – the keys that turn art to science. Aquaculture Asia Pacific Magazine 11(5):8-13. Poh, Y.T. 2015. Feed Management as the 4th Dimension in Shrimp Disease Prevention. www.slideshare.net/YongThongPoh/feedmanagemant-as-the-4th-dimension-in-shrimp-disease-prevention. FIGURE 6. Meticulous checking of feed tray to monitor exact feed amount is important. Note also the current shield up-current of the tray. FIGURE 8. Harvesting using cast nets. FIGURE 7. Harvest data of farm from 2011 to 2016. FIGURE 9. Harvested shrimp dripping dry before weighing.
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