prevalence and molecular characteristics of vibrio species in pre ...

More documents

Recommendations

Info

Table 2: World exports of shrimp International export of shrimp by FAO ISSCAAP (International Standard Statistical Classification of Aquatic Animal and Plant) Value 1986 1996 2006 Tonnes 938,102 1,601,147 3,244,871 US$ 1000 4,740,879 9,957,324 14,138,751 2.3 Shrimp consumption 8 Shrimp is considered a luxury food commodity because of its unique texture and flavour. According to reports (Bragagnolo and Rodriguez-Amaya, 2001), the high cholesterol content of shrimp is compensated by the very low total lipid content and the predominance of poly unsaturated fatty acids, especially the omega 3 fatty acid, which is important for human health. Another advantage of shrimp meat is the low mercury content when compared with other seafood. Consumer demand for shrimp is increasing in most developed countries. According to the reports of the United States National Marine Fisheries Service (NMFS) shrimp consumption per capita has increased over the years from an average of 1kg per year in 1989 to a record high of 1.8kg in 2005. Similarly, the European Union and Australia show a high consumer demand for the shrimp (Wan Norhana et al., 2010). 2. 4 Importance of pathogenic bacteria in shrimp production The presence of pathogenic bacteria in shrimp is closely related with environmental conditions and the microbiological quality of the water. Water temperature, salt content, distance between localization of catch and polluted areas, natural occurrence of bacteria in water, ingestion of food by the shrimp, method of catch and chilling conditions determine the number and the type of bacteria in the shrimp (Feldhusen, 2000).
9 Pathogenic bacteria associated with seafood can be categorized in to three groups (Feldhusen, 2000). These are Indigenous bacteria: Normal component of the marine and estuarine environment. Eg: V. cholerae, V. parahaemolyticus, V. vulnificus, Listeria monocytogenes, Clostridium botulinum, Aeromonas hydrophila (only virulent strains) Enteric bacteria: Due to contamination by the fecal material of animals and human Eg: Salmonella spp., pathogenic Escherichia coli, Shigella spp., Campylobacter spp., Yersinia enterocolitica (very few pathogenic sero types) Bacterial contamination during processing: (cross contamination) Bacillus cereus (only toxigenic strains), L. monocytogenes, Staphylococcus aureus, Clostridium perfringens. Although many pathogenic bacteria are associated with the shrimp production chain only a few organisms (Salmonella, Vibrio and Listeria) have been thoroughly studied for their prevalence and public health importance (Wan Norhana et al., 2010). Bhaskar et al. (1998) found Salmonella and Vibrio spp. in all the samples of shrimp, sediment, feed and pond water during the farming phase and at harvesting time. Listeria spp. was found only in clam meat during farming and sediment and shrimp at harvest. A study done in Sri Lanka revealed the prevalence of Salmonella in captured and cultured shrimp 14.44% and 11.11%, respectively, and Salmonella Newport was the highest (47.83%) among the deferent Salmonella serovars followed by Salmonella Weltevreden 8.7% (Kamalika et al., 2008). Samples of processed and unprocessed shrimp from processing plant in Nigeria was analyzed and revealed the presence of Bacillus spp., Salmonella spp., Shigella spp., Enterobacter spp., Micrococus spp., E. coli, Flavobacterium spp., Staphylococus aureus, Pseudomonas spp., Rhizopus spp., Aspergillus flavis, Aspergillus formigatus, Mucor mucido, and Sacchromyces spp., but no Vibrio spp. were isolated. This study showed a level of contamination by pathogenic bacteria that is hazardous for the consumer’s health (Okonko et al., 2008).
Page 1 and 2: 2.1 Shellfish culture CHAPTER II LI
Page 3: 7 constant over the years while cul
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 and 26: 29 host and effluent from the conta
Page 27 and 28: 31 elimination of Edwardsiella tard
Page 29 and 30: A. Cooling and freezing 33 Rapid an
Page 31: 2.10.3 Consumer education 35 Consum

prevalence and molecular characteristics of vibrio species in pre ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?