SummaryA study was conducted to investigate the influence of copper administration in ovo to chicken embryos and/or supplied in drinking water to growing chickens in the form copper nanoparticles (Cu-NP) or copper sulphate (CuSO 4 ). The fertilised eggs were assigned to three groups (n = 50 per group): control (not injected), injected with 50 mg/ kg Cu-NP or with 50 mg/kg CuSO 4 at day 1 of incubation. Thereafter, 126 one-day-
K E Y W O R D Sbroiler, growth performance, metabolic rate, nanoparticles