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

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farmers on good aquaculture practices, safe use of chemotherapeutic agents and good
handling practices.
Verification of HACCP plans for aquaculture production should be carried
out by qualified personnel to verify that the CCPs are satisfactory. Record keeping is
central to implementation in the HACCP system. The preparation of the HACCP plan,
updates, its implementation must be fully documented and records should be kept for
a period of two years and be available for inspection by a regular authority (Reilly and
Käferstein, 1997).
2.10.2 Post harvest stage
2.10.2.1 Post harvest handling
As shown in Table 7, optimum growth temperatures of the Vibrio are 37 °C.
Most of the shrimp producing countries are experiencing high environmental
temperatures that provide suitable temperatures for the growth of Vibrio spp. A study
reported that after harvest; V. parahaemolyticus multiply rapidly at 26 °C showing a
50-fold increase in 10h and 790-fold increase in 26 °C at 24 hours (Gooch et al.,
2002). An investigation was carried out of the post harvest surveillance for V.
vulnificus in post harvest oysters. It revealed the seasonal relationship with the density
of the organism. Low densities were observed in June, increasing through August and
becoming rare by September (La Valley et al., 2008). Therefore, it is most important
to immediately reduce and maintain the temperature of fresh post harvest shrimp at
low levels to prevent the multiplication of Vibrio to infectious levels.
2.10.2.2 Post harvest processing treatments
2.10.2.2.1 Thermal process
Thermal processes such as cold storage, freezing and low temperature
pasteurization have been reported effective in control the multiplication of Vibrio
organism.