Field efficacy of tulathromycin for the control of swine respiratory disease
Acute porcine pleuropneumonia caused by 'Actinobacillus pleuropneumoniae ' is a major cause of mortality, morbidity and decreased weight gain in pigs, particularly in the grower-finisher stage of production. Antimicrobial interventions through injection, or via the feed or water have been evaluated previously for control of this disease. Tulathromycin, a new macrolide antibiotic has been proven in challenge studies to provide adequate protection from this pathogen at a single injection for up to 9 days prior to exposure. These studies evaluated the efficiency of tulathromycin for controlling respiratory disease including 'A. pleuropneumoniae' infection in comparison to penicillin in three field settings. Tulathromycin lowered the rate of mortality and increased average daily gain (ADG) in pigs treated in an outbreak setting. Pigs treated near the end of a mild outbreak did not differ in ADG or survivability between treatments. Pigs treated after weaning in a barn with multi-factorial disease challenge only showed a difference in ADG and mortality within the first three weeks, and a greater increase in expected survival probability was seen in initially sick pigs compared to those that were initially healthy.