This study was composed of two experiments which investigated the response of two strains (Arbor Acre and Cobb 500, respectively) of broiler chickens to in ovo injection of inorganic salts of zinc, copper and their combination. A total of 300 hatching eggs [only 148 (59.20 %) and 232 (90.27 %), respectively, were fertile] each of Arbor Acre and Cobb 500 strains of broiler chickens were used in both experiments. These eggs were distributed into four treatments: control, in ovo inorganic Zn (80 µg.egg−1), Cu (16 µg.egg−1) and combined Zn and Cu (80 µg.egg−1 Zn and 16 µg.egg−1 Cu). The data obtained in both experiments were subjected to Completely Randomized Design (CRD) at the 5 % probability level. The results showed increased hatchability (P < 0.05) in eggs injected with the combination of inorganic salts of Zn and Cu in Experiment I and daily intake was influenced in both experiments. The carcass traits, organ development and gut morphometry were not significantly influenced by the treatment groups. The total serum protein and albumin of the birds were significantly (P < 0.05) increased by in ovo injection of inorganic salts of Zn and Cu at day 49 in the Experiment I. The study concluded that in ovo injection of inorganic salts of Zn at 80 µg.egg−1 and/or Cu at 16 µg. egg−1 could be adopted to increase feed intake with: attendant enhanced growth, enhanced immune response, increased albumin and total protein contents of blood serum in the strains of broiler chickens used.