Investigating the level of contamination of fresh Nile perch (lates niloticus) by escherichia coli and salmonella from lalle landing site, Arapai market and Soroti main market.

Abstract

Fish and fish products are a food with a high nutritional value, however fish may contain Escherichia coli and salmonella which cause foodborne infection out breaks in humans. The aim of the study was to identify and compare Escherichia. coli and salmonella in skin, muscles and intestine for fresh Nile fish samples collected Arapai market, Lalle landing site and Soroti main market. Fifteen fish samples were collected, 5 samples each from different traders and fishermen. MacConkey agar was used for isolation of Escherichia coli, Xylose Lysine Deoxycholate media (XLD) for isolation of salmonella, Escherichia coli was tested using idole ring test. The total coliform microbial load count from the Nile perch fish samples was higher than the standard mean log (2.00-6.00 cfu/g) required by UNBS hence this microbial count causes food poisoning hence fish were not recommended for human consumption. P-value (P≤0.05) indicate that there was a significant difference in total coliform count on hence implying that the different areas of study had different pathogens of food poisoning which would cause intoxication of fish. The mean log for microbial E-coli count was higher than the standard required by UNBS hence this microbial count causes food poisoning hence fish were not recommended for human consumption. The P value (P≥0.05) for the mean log for the microbial load of E-coli indicate that there was no significant difference of E-coli for the study areas. The mean log for salmonella was within the range of the standard mean log hence this microbial count does not cause food poisoning hence fish were recommended for human consumption. The P-value (P≥0.05) for the mean log of Salmonella shows that there was no significant difference in total microbial load of Salmonella hence implying that the different areas of study had statistically similar levels of microbial count of Salmonella which caused fish intoxication in these respective areas of study. It was concluded that total coliform microbial and E-coli count were higher than the standard recommended by UNBS however the count for salmonella was within the standard range hence the fish is recommended for human consumption. Therefore, more research should be done on Bacillus cereus count in Arapai market, Soroti and Lalle landing site.