This invention is related to the field of immunology of protein biotechnology and particularly to the construction of synthetic immunogens which result, where inoculated, in the production by cattle of an immune response capable of lesion to the ticks feeding on the inoculated bovines, reducing their number, their weight and their reproductive capacity to such an extent that the constructed immunogen can be used as an effective vaccine for tick control on bovines. The technical object of the invention consists of the design and construction of two synthetic immunogens constituted of a continuous and defined sequence with forty-three (43) amino acids, found in different positions in the sequence of protein Bm86, their polymerization with cysteine in the N-terminal and in the C-terminal, the medicamentous composition based on said peptide(s) and the synthetic vaccine obtained thereby.