Growth Performance of the African Catfish, Clarias gariepinus (Burchell), Fed Varying Inclusion Levels of Castor Seed ( Ricinus communis L.)

摘要

An 84 day feeding trial was conducted to evaluate raw and boiled castor seed (Ricinus communis L.) in the diet of Clarias gariepinus (Burchell, 1822) fingerlings with average body weight of 9.55 g ± 0.24 g. The fish were assigned to five treatments. The fish in five treatments, each replicated thrice, were fed with 37% crude protein experimental diets containing raw castor seed meal, (D1) and boiled seed diets subjected to boiling at 100oC for 20 (D2), 35 (D3), 50 (D4) and 65 (D5) minutes respectively. Diet1 (D1) served as control and was fed to the fish in the first treatment. Castor seeds served as an isonitrogenous source of protein in the experimental diets. There were no significant differences (p>0.05) in the Mean Weight Gain (MWG), Specific Growth Rate (SGR), Feed Conversion Ratio (FCR) and Protein Efficiency Ratio (PER) of the experimental fish fed diets D2, D3, D4 and D5. Highest percentage weight gain, SGR, FCR, PER, Net Protein Utilization (NPU) and digestibility rate were recorded in diet D4 containing castor seed boiled for 50 minutes at 100oC. Hence, boiling of castor seeds for 50 minutes at 100oC is considered the best approach for processing castor seeds through boiling.