GROWTH RESPONSE, NUTRIENT UTILIZATION, AND HEALTH PARAMETERS OF Clarias gariepinus (Burchell, 1822) FED VARIOUS LEVELS OF SOAKED AND FERMENTED Enterolobiumcyclocarpum LEAF

Abstract

ABSTRACT High cost of conventional dietary protein ingredients sources such as soybean meal, in aquafeed production necessitates the exploration of cost-effective and locally available alternatives with limited relevance in human diet. This study investigated the performance, nutrient utilization and health of Clarias gariepinus fingerlings fed diets with graded (0, 10, 20, and 30%) levels of soaked and fermented Enterolobiumcyclocarpum leaf meal. Seven isonitrogenous (40% crude protein) and isoenergetic (314kcal) diets were formulated,the control diet without either meal and designated as TS1–TS3 (10%, 20%, 30% SEcLM) and TF1–TF3 (10%, 20%, 30% FEcLM). The feeds were fed to triplicate groups of fish at 3% body weight daily for eight weeks. Growth, feed conversion ratio (FCR), specific growth rate (SGR), protein efficiency ratio and apparent protein digestibility (APD) parameters were monitored weekly. Blood samples were collected from each group for haematology and blood chemistry analyses, while the liver and mid gut were observed for histopathological studies. Data obtained were analysed using descriptive and inferential statistics. Results showed that fish fed TF2 (20% FEcLM) and TF3 (30% FEcLM) achieved superior growth compared to the control. Final body weight for TF3 (13.85 g) and TF2 (13.12 g) significantly exceeded that of the control group (12.42 g). Specific Growth Rate (SGR) was highest in TF3 (2.09%/day), compared to 1.91%/day in the control. Feed Conversion Ratio (FCR) also improved in TF3 (1.54), over the group fed the control (1.70). Protein Efficiency Ratio (PER) peaked in the group of fish fedTF3 (2.67), also surpassing the control diet (2.40). These results suggest that fermentation enhanced the nutritional quality of E. cyclocarpum leaves, likely by reducing anti-nutritional factors, improving nutrient value and nutrient availability. Haematological parameters remained within normal physiological ranges, indicating no adverse health effects. Packed Cell Volume (PCV) was highest in TF3 (31.3%) and TF2 (30.6%), compared to the control (27.6%). Haemoglobin concentration also followed this trend, with TF3 and TF2 recording 7.8 g/dl and 7.6 g/dl, respectively, versus 6.9 g/dl in the control group. Red Blood Cell (RBC) counts were 2.64 ×10¹²/L and 2.51 ×10¹²/L in TF3 and TF2, respectively, which were higher than the control (2.21 ×10¹²/L). White Blood Cell (WBC) levels remained stable across treatments, suggesting no immunological stress. Histological examination revealed no significant lesions in the liver and intestinal tissues of fish fed diets up to 20% FEcLM, though mild hepatocellular atrophy and enterocyte degeneration were observed at 30% inclusion in the soaked groups. Gut histomorphometry supported better nutrient absorption in the fermented groups, as evidenced by higher villi height and crypt depth. In conclusion, E. cyclocarpum leaf meal, particularly when fermented, can replace soybean meal in C. gariepinus diets at levels up to 30% without compromising growth or health.