Tilmicosin is a macrolide antibiotic developed for veterinary use. It is recommended for treatment and prevention of pneumonia in cattle, sheep and pigs, associated with Pasteurella haemolytica, P. multocida, Actinobacillus pleuropneumoniae, mycoplasma species and other microorganisms found sensitive to this compound. It is an antibiotic medicine with great antibiotic effect and broad antibiotic spectrum . Not show resistance and cross-resistance with other antibiotic often used in clinic. Mainly used in the Pleuropneumonia and the infection caused by Pasteurellaceae , Pasteurella and mycoplasma.