Occurrence of Salmonella spp. from fresh fish (Tilapia nilotica Linn) using improved isolation methods.

Fresh fish (Tilapia Nilotica Linn) is a very important source of protein to the population in our country; this is of importance when other sources of animal protein are in short-supply. This freshwater fish may harbor salmonella spp. Which may be a source of pathogen to human hence, this study is important due to the public health implications. A total of 90 samples (30 whole freshwater fish, 30 intestines and 30 gills) were collected from different open market in Aba, South, Aba North and Osisioma Local Government Area all in Abia State, and examined. The objective of this study was to compare between non-pellet method and pellet method of isolation of salmonella spp. from different parts of freshwater fish. In this study, the pellet method was evaluated and compared with the non-pellet. Three selective agars used for the purpose of this study namely: Salmonella-shigella Agar (SSA) xylose Lysine Deoxycholate Agar (XLD) and Bismuth sulfite Agar (BSA). There was significance difference (P<0.05) with the pellet method on the 30 Tilapia sample. The frequency of occurrence in pellet method was 66.66%, 50.00% and 26.66% growth on SSA, XLD and BSA while non-pellet method presented occurrence of 33.33%, 23.33% and 13.30% for SSA, XLD and BSA respectively. It was observed that salmonella sp was found more on the whole body of Tilapia nilotica than the gill and intestine presenting 66.66%, 50.00% and 20.00% respectively. The result confirms that pellet method isolated higher number of salmonella sp than non – pellet method.