Abstract
Brazil is in fourth place in the ranking of the world's export of pork, representing 10% of the whole volume exported, reaching a profit of about 1 billion US$ per year. The Swine Enzootic Pneumonia (PES) or Mycoplasmal Swine Pneumonia, caused by the fastidious bacterium Mycoplasma hyopneumoniae, is one of the main respiratory diseases of swine. M. hyopneumoniae destroys the main nonspeci…