<p>Zinc oxide nanoparticles (ZnO–NPs) are increasingly studied for their applications in agriculture and animal husbandry due to their unique physicochemical properties, including high bioavailability and biocompatibility. This study aims to explore not only the direct benefits of ZnO–NPs on poultry performance but also their broader implications for economic sustainability. ZnO–NPs were synthesized via the sol-gel method and subsequently characterized to determine their physicochemical properties and general cytotoxicity prior to application in vivo. Broiler chickens were then fed diets supplemented with ZnO–NPs to evaluate growth performance, mortality rates, blood biochemical parameters, and immune responses. The results demonstrated that ZnO–NPs improved feed efficiency and reduced mortality rates. Furthermore, ZnO–NP supplementation showed no adverse effects on critical internal organs or blood metabolites. This analysis highlights the potential of ZnO–NPs as a sustainable substitute for traditional zinc oxide (ZnO) in poultry nutrition.</p>