Necrotic enteritis, caused by Clostridium perfringens type A and type C, remains a significant challenge for poultry production, resulting in substantial economic losses globally. This study investigated the potential of cumin oil nano emulsion as a novel vaccine adjuvant for C. perfringens type A, comparing its efficacy to the conventional aluminium hydroxide gel adjuvant. Toxoid vaccines were prepared using three adjuvant formulations: cumin oil nano emulsion at 50:50 and 30:70 ratios and aluminium hydroxide gel at a ratio 20: 80. The vaccines were assessed for sterility, safety, and immunogenicity. Sterility testing confirmed all formulations were free from contaminants. Safety trials in specific-pathogen-free (SPF) chicks demonstrated no adverse reactions, confirming the biocompatibility of cumin oil nano emulsion. Immunogenicity was evaluated through toxin neutralization tests, with antibody titres measured over five weeks post-vaccination. Vaccines adjuvanted with cumin oil nano emulsion induced robust and sustained antitoxin responses, reaching peak titres of 60 IU/ml, comparable to the aluminium hydroxide gel vaccine. These findings underscore the potential of cumin oil nano emulsion as an effective alternative to traditional adjuvants, leveraging its immunomodulatory and antimicrobial properties to enhance vaccine efficacy. Moreover, the use of natural oil-based adjuvants aligns with the increasing demand for sustainable and safer vaccine formulations in the poultry industry. Further studies are recommended to optimize the formulation and evaluate the long-term immunity conferred by cumin oil-adjuvanted vaccines. This research highlights a promising step toward innovative adjuvant solutions for controlling C. perfringens-associated diseases in poultry |