Dietary implications of toasted Jatropha curcas seed: Insight on zootechnical and hematological parameters of Clarias gariepinus

Jatropha curcas seeds (JCS) have high crude protein and excellent amino acid profile. However, JCS contain antinutrients which affect the health of animals fed with it negatively. Therefore, this study evaluated toasting at varying durations (0, 10, 20, and 30 min) as a means of detoxifying the JCS, and evaluated the health implication and nutritional characteristics of Clarias gariepinus fed diets included with the seeds (35% CP; 315 kcal/g). The nutritional profile of the JCS was substantially improved by decreasing antinutrients with prolonged duration of processing by toasting (i.e., between 10 and 30 min). However, protein seems to be substantially reduced beyond the 20 th minute of treatment. The fish fed the toasted seed also performed better than the control in terms of growth and survival. The second-order polynomial regression analysis estimates that 24 min was optimum for toasting the JCS to attain maximum dietary utilization by the fish. Aside from the carcass protein deposition that was significantly higher, hematological parameters such as hematocrit (23%), hemoglobin (7.7 g/dL), and red blood cell (1.2 × 10 6 cells/mm 3 ) were higher in treatments with prolonged toasting (i.e., 20 min above) compared with others and raw JCS. In the same vein, it was estimated that it will cost less to culture 1 kg of the catfish using the toasted JCS compared to the raw JCS. It was concluded that the processing of JCS by toasting should not exceed 24 min to improve the health and dietary utilization by catfish.