The present study aimed to detect and characterize antigenic proteins and to assess their activity as preventive vaccines against dermatobiosis. Polyclonal antibodies were produced against three larval instars (L(1), L(2), L(3)), and their antigenic proteins were assessed for reactivity. Polyclonal antibodies produced in animals immunized with extracts were analyzed, and L(3)-derived antibodies showed proteins with better antigenic responses. The study of reactivity using immunodetection showed that the 50-kDa protein had the highest antigenicity. This protein was purified and subjected to mass spectrometry, and the sequences obtained were compared with those in the databases available. No similarities were found with existing sequences. Subsequently, large quantities of purified protein were used to immunize cattle. Vaccine effectiveness was evaluated by comparing the number of cutaneous nodules formed in the control group and immunized animals. The antigen produced proved a promising candidate for vaccine production, with 90.67 % efficacy. Immunohistochemistry of antigen-antibody reaction in larval sections showed epitopes all over larval tissues.