A study was carried out to investigate the bacterial load and the occurrence of potential pathogens from healthy Tilapia guineensis. Thirty samples of Tilapia guineensis were collected from Awoye coastal environment, Ondo state Nigeria. The skin and the gills of the fish were examined. The samples were collected by swabbing aseptically over the skin and gills area of the fish and then processed for bacterial count, followed by isolation and identification of potential pathogens. Microbial load analysis revealed that the total viable count of bacteria ranged from 1.5 – 7.6 x 107 cfu/ml for skin and 2.1 – 6.4 x 106 cfu/ml for gills. The results show that the bacterial load of tilapia samples falls within the standard microbiological acceptable limit. There was no significant variation (P > 0.05) in the bacterial load from the skin and gills segment of the fish, and water sample studied. The biochemical identification tests of the bacterial isolates confirm the presence of the following enterics bacteria: Escherichia coli, Citrobacter freundi, Serratia mercescens, Klebsiella sp., Provindencia rettgeri, Shigella sonnei, Citrobacter amalonaticus, Morganella morganii, Proteus sp., Enterobacter aerogens, Enterobacter Cloacae, Citrobacter diversus. The percentage frequency of occurrence shows that E. coli recorded the highest frequency of occurrence of 20%, followed by Klebsiella sp. with 15% occurrence and Serratia mercescens with 12.50%. Morganella morgani, Shigella sonnei and Proteus sp. showed the least frequency of occurrence with 2.50% and 5% occurrence each respectively. This study therefore reveals the bacterial load of Tilapia guineensis with a view to provide information on the state of the environment and level of water contamination as well as the security and/or insecurity nature of fish when consumed.

Keywords: Tilapia guineensis, bacterial load, Skin, Gills, Pathogen.

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