Observations on experimental inactivated vaccines for contagious bovine pleuropneumonia.

In two trials the efficacy of inactivated vaccines against contagious bovine pleuropneumonia was tested by exposing vaccinated cattle to droplet infection provided by close contact with experimentally infected 'donors'. Complete protection was given by an extreme form of vaccination in which a heavy suspension of killed Mycoplasma mycoides subsp. mycoides emulsified with Freund's complete adjuvant was given in two large doses.