**Contaminated feed**

Improperly stored feed or feed prepared on a farm under poor hygienic conditions can be a source of *Salmonella*.

### **Contaminated source water**

The water used in growout ponds, cages or tanks can be contaminated with *Salmonella* through wildlife runoff, untreated domestic sewage, discharge from animal farms, etc.

#### **On farm primary processing**

Aquaculture products can become contaminated with *Salmonella* through the use of unsanitary ice, water, containers, and poor hygienic handling practices (FAO, 2010).

For example, for shrimp processing industry the information from literature indicates that the principal sources of *Salmonella* contamination are culture ponds, coastal water used for handling and processing of seafood (Hariyadi et al., 2005; Shabarinath et al., 2007; Upadhyay et al., 2010). Similarly, Pal and Marshall (2009) reported that the potential source of *Salmonella* contamination in farm-raised catfish is likely due to poor water quality, farm runoff, fecal contamination from wild animals or livestock, feed processing under poor sanitary conditions or distribution, retail marketing, and handling/preparation practices.

Ray et al.,(1976) reported that the potential hazard in cooked fishery product is cross contamination of the cooked products with raw fishery product which might occur under commercial processing condition. Thus, good sanitation practices on the unloading docks and during transport to the processing facility are essential for preventing product contamination. The use of contaminated ice or uncleaned holding facilities may also contribute to the product contaminant load (Gecan et al., 1988). As a result, many factors including inadequate supplies of clean water, inadequate sanitary measures, lack of food hygiene and food safety measures have been responsible for increased incidence of foodborne salmonellosis (Shabarinath et al., 2007).

Deep-sea fish are generally *Salmonella* sp. free but susceptible to contamination post-catch. Water temperature has been

proposed as playing an important role in the long-term survival of *Salmonella* in the environment (FAO, 2010). In raw seafood products mainly from tropical climates, there is a high prevalence of *Salmonella* whereas low prevalence or absence can be common in temperate regions (Millard and Rocklif, 2004).
