Evaluating Alternative Feed Additives: The Role of Caulerpa race-mosa and Probiotics in Enhancing Catfish (Clarias gariepinus) Aqua-culture Performance

This study evaluated the effects of Caulerpa racemosa and probiotics on the growth performance, survival, and feed utilisation of African catfish (Clarias gariepinus) fingerlings. Four treatments were formulated: A (25g C. racemosa + 6mL probiotics), B (50g C. racemosa + 6mL probiotics), C (75g C. racemosa + 6mL probiotics), and D (control, no additives). The highest weight gain (27.80±1.62g) and most efficient feed conversion ratio (FCR) were observed in the control group, attributed to its optimal protein (17.82%) and fat (10.51%) content. Treatment A yielded moderate growth (19.35±2.45g) with the lowest FCR (1.62±0.03), indicating a potential synergistic effect of low-level C. racemosa and probiotics. In contrast, Treatments B and C resulted in reduced growth (17.72±0.47g and 16.92±1.09g, respectively), likely due to high levels of dietary carbohydrate (up to 61.56%) and ash (up to 24.25%), which impaired nutrient assimilation. Survival rates were uniformly high across treatments (93.3–100%), confirming the safety of these additives. The findings underscore the importance of dosage in functional feed formulations, highlighting that excessive seaweed inclusion may compromise performance, while low-level supplementation in combination with probiotics offers promising benefits for sustainable aquaculture.