The zinc element (Zn) is one of the micronutrients and an essential element of the body which has some deleterious and irreparable effects on growth in case of lack it. Thus, we aimed to assess IGF-1 in goldfish with Zn deficiency and to investigate the effect of Zn supplementation on these parameters. Goldfish  (Carassius auratus)  juvenile  (3.5 g)  were fed purified diets based on casein as ...