Proximate and Mineral Composition of Tilapia Fish Species Harvested from Kainji Lake, Niger State

Fish serves as a critical source of dietary protein and essential minerals for communities in North Central Nigeria, particularly those dependent on inland water bodies for subsistence fishing. This study determined the proximate and mineral composition of three tilapia species, namely Oreochromis niloticus, Sarotherodon galilaeus, and Tilapia zillii, harvested from Kainji Lake in Niger State. Fresh specimens were obtained from artisanal fishers operating on the lake, processed under controlled conditions, and analysed for moisture, crude protein, crude fat, crude fibre, total ash, and nitrogen-free extract using standard AOAC methods. Mineral analysis was conducted by atomic absorption spectrophotometry for calcium, phosphorus, potassium, iron, zinc, and selenium after dry ashing. Crude protein content ranged from 18.4 to 21.6 percent across species, confirming fish as a high-quality protein source. Crude fat content varied from 2.1 to 4.8 percent, indicating a lean fish composition suitable for calorie-conscious diets. Calcium was highest in Oreochromis niloticus at 1,248 mg/100g, while iron was most abundant in Sarotherodon galilaeus at 3.4 mg/100g. Zinc concentrations ranged from 0.8 to 2.1 mg/100g. Selenium was detected in all species at nutritionally meaningful levels. These results confirm that tilapia species from Kainji Lake constitute nutritionally valuable food resources. The findings support policy promotion of artisanal fisheries in Niger State as a strategy to combat protein-energy malnutrition in North Central Nigeria.

Keywords: tilapia fish, proximate composition, mineral analysis, Kainji Lake, Niger State