EFFECTS OF MELAMINE AND CYANURIC ACID ON GROWTH, SKIN COLOR AND HISTOLOGICAL CHANGES IN THE KIDNEY OF HYBRID CLARIAS CATFISH

Abstract

The effects of dietary supplementation of melamine (MEL) and cyanuric acid (CYA) on growth performance, feed utilization and histological changes in hybrid Clarias catfish, Clarias macrocephalus × C. gariepinus were evaluated. Five isonitrogenous (35% crude protein) and isolipidic (8% lipid) experimental diets were formulated as follows: Diet 1 (without MEL and CYA served as control diet); diets 2-3 (with MEL and CYA at, 5+5 and 10+10 g/kg diet, respectively); diet 4 (with only MEL at 10 g/kg diet); and diet 5 (with CYA alone at 10 g/kg diet). Experimental diets were randomly assigned to three replicate tanks and fed to hybrid Clarias catfish (mean initial weight 2.5 g) for 4 weeks. The results from this study indicated that all the diets with MEL and CYA singly or in combination had adverse effects on growth performance and feed utilization compared to fish fed the control diet. Moreover, MEL and CYA induced darkening skin coloration. The inclusion of MEL and CYA affected kidney tissues of fish. Golden-brown melamine–cyanurate crystals were recorded in the kidney of fish with combined MEL and CYA supplementation. This study provides the understanding of toxicity and pathological changes in hybrid Clarias catfish exposed to MEL and CYA.