Evaluation of Growth Performance of Catfish (Clarias gariepinus) Fed Varying Levels of Soybean Meal as Fishmeal Replacement in Ogun State

The high and volatile cost of fishmeal has compelled fish farmers in South West Nigeria to explore alternative protein sources for catfish diets. This study evaluates the growth performance, feed utilisation, and survival rate of juvenile African catfish fed diets in which soybean meal replaces fishmeal at levels of 0%, 25%, 50%, 75%, and 100%. The experiment was conducted at a commercial fish farm in Abeokuta, Ogun State, over eight weeks using 150 uniform juveniles with an initial mean weight of 12.4 g. Fish were distributed into 15 plastic tanks and fed twice daily to apparent satiation. Final mean weight, weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio, and survival rate were recorded at the end of the trial. Results showed that fish fed 25% soybean meal replacement recorded specific growth rate and feed conversion ratio values comparable to the control group. Performance declined significantly at substitution levels above 50%, attributed to the presence of anti-nutritional factors and reduced protein digestibility. Survival rates were above 90% across all treatment groups. The study concludes that soybean meal can effectively replace fishmeal at up to 25% without adverse effects on growth or feed utilisation in African catfish juveniles. This finding has direct cost reduction implications for catfish farmers in Ogun State operating under current fishmeal market conditions.

Keywords: Clarias gariepinus, soybean meal, fishmeal replacement, growth performance, Ogun State