A total of 200 1-week-old Japanese quails were randomly allocated into five treatment groups, each consisting of 40 unsexed birds (five replicates, eight birds each). Quails were reared in traditional cages (90 Â 40 Â 40 cm), and feed and water were made available throughout the 5-week trial. The treatment groups were as follows: the 1st was fed basal diet, whereas the 2nd, 3rd, 4th, and 5th groups were fed with ration supplemented with nano zinc (Zn-NPs) at doses of 0.1, 0.2, 0.3, and 0.4 g/kg diet, respectively. Results showed that, a significant (p .0001) improvement in body weight, weight gain, feed intake, and feed conversion ratio was observed in birds fed diets supplemented with 0.2 g/kg of Zn-NPs. Supplementation of Zn-NPs at doses of 0.1-0.3 g/kg diet demonstrated a positive impact on the activity of ALT, AST, and LDH. The liver profile parameters were not statistically influenced (p > .05) by dietary biological nano zinc, with the exception of total cholesterol (TC), high density lipoprotein (HDL), and low density lipoprotein (LDL). Also, dietary supplementation of biological Zn-NPs at concentrations of 0.1-0.3 g/kg diet demonstrated a positive impact on superoxide dismutase (SOD), glutathione peroxidase (GPX), malondialdehyde (MDA), immunoglobulin G (IgG), and immunoglobulin M (IgM). Dietary supplementation of Zn-NPs led to an increase in beneficial microbial populations. From the obtained results, Zn-NPs supplementation at 0.2 g/kg diet had a positive effect on the performance and physiological status of growing Japanese quails.
HIGHLIGHTSZinc (Zn) is an important trace element for the general functioning of the animal body. A significant improvement in growth performance was observed in birds fed diet enriched with 0.2 g/kg of Zn-NPs. Supplementation of Zn-NPs (0.1-0.3 g/kg diet) demonstrated a positive impact on immunity and antioxidant indices ARTICLE HISTORY
