The present invention relates to methods for treating or preventing a disease or disorder in an animal caused by infection by Mycoplasma hyopneumoniae (M. hyo) by administering to the animal at approximately three (3) to ten (10) days of age, a single dose of an effective amount of a M. hyo vaccine. The M. hyo vaccine can be a whole or partial cell inactivated or modified live preparation, a subunit vaccine, or a nucleic acid or DNA vaccine. The M. hyo vaccine administered in accordance with the present invention can be synthesized or recombinantly produced.