Cost-Effectiveness and Growth Performance of Clarias gariepinus Fingerlings Fed Formulated Diets Containing Enzyme and Probiotic Additives Compared with a Commercial Feed

Feed cost and growth performance are the two most decisive factors in the profitability of African catfish (Clarias gariepinus) production, given that feed accounts for 60–70% of total operating costs. This study compared the cost of formulating 8.34 kg of three locally compounded 45% crude protein diets one containing a commercial enzyme (Maxigrain®), one containing a commercial probiotic (Biogut® Aqua), and one without either additive against the cost of an equivalent quantity of a commercial feed (Blue Crown®), and evaluated the growth performance and feed utilisation of C. gariepinus fingerlings fed the four diets over sixteen weeks. Formulating the enzyme diet (T1), probiotic diet (T2) and additive-free diet (T4) cost ₦24,275, ₦24,345 and ₦24,175 respectively, roughly 19–24% less than the ₦30,190 cost of an equivalent amount of Blue Crown® (T3). Fish fed the enzyme diet (T1) achieved the highest final weight (35.73 g) and weight gain (32.93 g), followed by the probiotic diet (T2) (31.69 g; 29.46 g); both outperformed the commercial feed (T3), which produced the lowest final weight (14.27 g) and weight gain (11.87 g). The probiotic diet (T2) produced the best specific growth rate (2.61%/day) and the most favourable feed conversion ratio (0.43) and feed conversion efficiency (234.58). These results indicate that locally formulated diets supplemented with enzyme or probiotic additives were both cheaper to produce and more effective in promoting growth than the commercial feed evaluated, supporting their adoption as cost-effective alternatives for small- and medium-scale catfish farmers.