Dietary Lysine Requirement of the African Catfish, Clarias gariepinus

Abstract

A growth study was conducted to quantify the dietary lysine requirement of the African catfish, Clarias gariepinus. Diets incorporating case in and gelatin as sources of intact protein, supplemented with crystalline amino acids, were formulated to a crude protein content of 400 g/kg and gross energy content of 12 kJ/g dry matter. Diets with graded levels of lysine (40-65 g/kg protein) were formulated and fed to triplicate groups of African catfish (15.4 ± 1.6 g) twice a day up to satiation for 70 days. Dietary lysine requirement estimated using break point analysis was 57 g/kg dietary protein. This information is useful in developing cost-efficient research diets and practical feeds for African catfish.