Nyan Taw
Former Chief Technical Advisor & Consultant for FAO of the UN and Consultant for World Bank Projects, Malaysia.
Title: Sustainable Shrimp Farming in Biosecure RAS and Biofloc Technology: Commercial Experience and Approaches to Disease Control-Malaysia
Biography
Biography: Nyan Taw
Abstract
Biosecure Biofloc technology applied in shrimp farming is adapted from the basic minimum water exchange shrimp intensive culture system used in Indonesia since early late 1990s. The system then was to position aerators within culture ponds to concentrate waste (sludge) into centre of ponds which were then siphon out physically or through central drain system. The aerators were operated almost 24 hours to have optimum culture pond environmental condition. The system creates clean water column and bottom feeding area and separated the sludge area (Taw, 2005; 2015, Taw, et al 2007). Shrimp bio-floc system is somewhat an upgraded system by introducing carbon such as molasses and wheat flour to develop a heterotrophic environment with zero water exchange which suspend bio-floc colony within pond water column. The bio-floc system is developed by developing algae first and later cross over to bio-floc to have self-nitrification process sets in (Taw 2014). Main economic benefits of shrimp bio-floc system are – better biosecurity, low FCR, higher production, higher energy efficiency and sustainable production. Biofloc system alone cannot prevent ever emerging shrimp diseases. However, bio-floc and bio-secure shrimp farm design, construction and operation system have shown to prevent diseases entering the farm facilities (Taw 2005; Taw et al 2008, & Taw & Setio 2014). In Malaysia bio-secure modular RAS system with bio-floc technology has been applied at Blue Archipelago shrimp farm since October 2011 and has been operating successfully without any incident of EMS/AHPND which was a major threat to China, Vietnam, Malaysia and Thailand (Taw, et al. 2013 & Taw 2014). According to In-Kwon (2012 &2014) there were more than 2,000 bacterial species in well-developed bio-floc water. This bio-floc may enhance immune activity based on mRNA expression of six immune-related genes – ProPO1, ProPO2, PPAE, ran, mas and SP1. A study at Bogor University, Indonesia and Ghent University, Belgium revealed that bio-floc system contributes to the enhancement of immune response and survival after IMNV challenge regardless the carbon source. The application of BFT brings about beneficial effect in disease control and management in shrimp culture (Ekasari, et al., 2014).