This study aims to identify novel candidates for the development of serotyping assays for Toxoplasma gondii (T. gondii). We employed an in vivo approach, utilizing co-immunoprecipitation (Co-IP) with sera from infected mice to identify antigenic proteins, followed by detection via LC-MS/MS. Additionally, an in silico analysis was conducted to explore the genetic polymorphism of the genes encoding these proteins and to determine mutations associated with specific genotypes.