Evaluation of chelated iron and iron sulfate in the diet of African catfish, Clarias gariepinus to enhance iron excretion for application in integrated aquaponics systems

Abstract

AbstractThe best source and inclusion level of iron from feed additives for optimizing the production of African catfish was determined while simultaneously evaluating excretion of effluent that can be used to optimally grow plants in aquaponics systems. Using six experimental treatments and a control, the production parameters, proximate composition, hematological indices, nonspecific immunity, tissue mineral composition, apparent digestibility coefficients, and water quality trials were examined. Mineral sources were iron from an organic source, chelated amino acid, and an inorganic source, iron phosphate. No significant differences were observed in production parameters. There were differences in proximate composition. Fish fed FeSO4 at 30 mg/kg had significantly higher hematocrit levels and red blood cell levels compared with the control, while FeSO4 60 had the highest hemoglobin levels. Tissue mineral composition showed significantly higher iron concentrations in the liver of the control compared with all the treatments. FeSO4 30 treatment had the highest apparent digestibility coefficient (96%). Iron concentrations in the effluent of the water differed between treatments. Iron from FeSO4 can improve the hematological profile of catfish compared with the control, and its effluent from culture water has the potential to minimize or reduce the use of nutrient fertilizers in integrated aquaponics systems.