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30 digestion, improves water quality, or stimulate the immune system of the host (Verschuere et al., 2000). Microorganism belonging to photosynthetic bacteria, Nitromonas spp., Lactobacillus spp., yeast, Bacillus spp., Pseudomonas fluorescens, Streptococcus faecium, Tetraselmis succia and other bacteria have been tested as probiotics (Wang et al., 2005). Several studies have been carried out to determine the effectiveness of probiotics on aquaculture. Rengpipat et al. (1998) reported the use of Bacillus strain S11 as a probiotic in black tiger (P. monodon) shrimp culture. After a 100 day feeding trial with probiotic supplements and non-supplement feed, P. monodon challenged with pathogenic V. harveyi strain D331 by immersing the shrimp. Ten days later, all the shrimp groups treated with probiotics showed 100% survival and the control group had 26% survival (Rengpipat et al., 1998). Similar research was carried out in shrimp ponds in the Philippines where the losses due to luminas Vibrio (V. harveyi) are catastrophic. Bacillus spp. used as probiotics and experienced a higher survival rate (80-100%) in treated farms (Moriarty, 1999). Investigations carried out to determine the effectiveness of probiotics on white shrimp (P. vannamei) found a noticeable influence on the shrimp production and an increase in the water quality by reducing concentration of nitrogen and phosphorous. A study found that the average count of Bacillus spp., amonifying bacteria and protein mineralizing bacteria were significantly higher in probiotic treated ponds compared to control ponds. Furthermore, it increased dissolved oxygen and reduced dissolved reactive- phosphorus, total inorganic nitrogen and chemical oxygen demand. Shrimp production and survival rate also increased in treated ponds. The results were average 8215± 265 kg shrimp/ ha and a survival rate of 81.0 ± 6.75% in treated ponds compared with 4985± 503 kg shrimp/ ha and 48.67± 3.51% respectively in control ponds (Wang et al., 2005). Ma et al. (2009) tested strains of Lactobacillus spp. JK-8 and JK-11 for their ability to remove pathogenic bacteria and nitrogen compounds. Cell-free supernatants concentrated from pH-non adjusted JK-8cultures and either pH-adjusted or non adjusted JK-11 cultures demonstrated remarkable antimicrobial activities against pathogenic bacteria. Vibrio parahaemolyticus and V. harveyi, were significantly susceptible and destroy within 30 minute exposure. Complete
31 elimination of Edwardsiella tarda, S. aureus, Salmonella and Shigella were achieved within 1.5 hrs and E. coli and S. pyrogenes were completely killed within 2-3 hrs under same condition. Simultaneously, both JK-8 and JK-11 culture facilitated the removal of different nitrogen compounds (e.g. NH + 4, NO - 2, and NO - 3) up to 400 µM. 2.10.1.3 HACCP application The use of hazard analysis critical control point (HACCP) as a means of controlling food borne pathogens in the food industry is gaining acceptance internationally both by industry and regulatory agencies. Food manufacturers can identify steps for preventing, controlling or eliminating hazards associated with their product and minimize the potential food safety problems (Buchanan, 1995). HACCP in shrimp farms can include all steps from the “farm to table” such as, production and handling of raw materials, processing operation, processing environment, handling and storage practices, and distribution activities (Tookwinas and Keerativiriyaporn, 2004). A good aquaculture practice is a prerequisite for the implementing HACCP. Good aquaculture practices are defined as those practices of the aquaculture sector that are necessary to produce quality food products, conforming to food law and regulations. Conducting hazard analysis, determine critical control points (CCP), establish critical limits, establish a system to monitor control of CCP, establish the corrective action, establish procedures for verification and establish documentation are the main 7 steps included in the HACCP system (Reilly and Käferstein, 1997). Reilly and Käferstein (1997) identified four critical control points in the aquaculture farming. Those are site selection, water supply, feed supply and production/grow out stage, and explained the control and verification methods for each step. Farm management, feed production and farming practices are the CCP that have been studied by Tookwinas and Keerativiriyaporn (2004) and preventive measures applied in shrimp farming in Thailand are i). Farm registration; ii). Control the uses of feed/antibiotics; iii). Monitor residues in products from farm; iv). Mobile unit control of diseases; use of antibiotics and feed; v). Monitoring the quality of water (both inlet and outlet); vi). Inspect farm hygiene and post harvest handling practices; vii). Train
Page 1 and 2: 2.1 Shellfish culture CHAPTER II LI
Page 3 and 4: 7 constant over the years while cul
Page 5 and 6: 9 Pathogenic bacteria associated wi
Page 7 and 8: 11 Listeriosis, and other pathogens
Page 9 and 10: Coastal water Shrimp Bangladesh (Co
Page 11 and 12: Table 4: Cholera pandemics Pandemic
Page 13 and 14: 17 parahaemolyticus should be Kanag
Page 15 and 16: 19 2.7.2 Biochemical characteristic
Page 17 and 18: 21 2.7.4 Genotypic characteristics
Page 19 and 20: 23 Clinical strains of V. parahaemo
Page 21 and 22: 2.8 Human pathogenic Vibrio 2.8.1 V
Page 23 and 24: 27 Vibrio spp. display similar bioc
Page 25: 29 host and effluent from the conta
Page 29 and 30: A. Cooling and freezing 33 Rapid an
Page 31: 2.10.3 Consumer education 35 Consum

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