cell line was derived from the kidney tissue of an adult female cocker spaniel. However, the MDCK cell line is known to the person skilled in the art. Thus, according to one aspect, the present application provides a method for the preparation of an immunogenic composition for the treatment and/or prophylaxis of mycoplasma infections in a subject comprising a) cultivation of mycoplasma bacteria in a serum-reduced or swine serum free, eukaryotic cell system; b) obtaining an antigen of the mycoplasma bacteria; and c) addition of a pharmaceutically acceptable carrier,