Estimating the comparative clinical and economic consequences of tulathromycin for treatment of present or anticipated outbreaks of bovine respiratory disease in feedlot cattle in the United States.

The goal of this study was to determine the clinical and economic impact of using tulathromycin as first line treatment for bovine respiratory disease (BRD) compared with other commonly used antimicrobials. Two decision trees were developed simulating the consequences of treating cattle at high risk of developing BRD [control model (CM)] or cattle with first clinical BRD episode [treatment model (TM)]. As comparators florfenicol and tilmicosin were considered in both models whereas enrofloxacin was included in the TM because it was only labeled for treatment of BRD at the time of development of the calculators. A total of 5 (CM) and 10 (TM) comparative clinical studies that reported efficacy data for the selected drugs and indications were identified as suitable for model population. The following outcomes were considered: first treatment success, number of subsequent BRD treatments, chronics, and mortalities. Cost parameters were considered from the perspective of the producer and included treatment costs (first treatment and retreatments) and costs of chronics and deaths derived from published sources for 2010 (default). The models allowed the estimation of clinical and economic consequences according to each individual trial outcomes. Treatment with tulathromycin resulted in more first treatment successes and fewer removals (chronics and deaths) in all comparisons. The average total number of antimicrobial treatments required for the management of BRD was also least with tulathromycin as first treatment option. Because of better efficacy, total costs over the entire study periods were always lowest with tulathromycin. Depending on the study selected as the basis for the efficacy evaluation, cost savings with tulathromycin were calculated in the CM between US$21.00 and $47.86 (vs. florfenicol) and $11.37 and $72.64 (vs. tilmicosin); cost savings in the TM ranged between $28.47 and $143.87 (vs. florfenicol) and $7.75 and $84.91 (vs. tilmicosin) as well as between $23.22 and $47.82 (vs. enrofloxacin), with the ranges reflecting a variety of settings in different trials. Thus, the higher drug costs of tulathromycin were more than offset by reduced BRD treatments, chronics, and mortalities in the herd. Fewer BRD episodes in cattle treated with tulathromycin not only contributes to overall savings in BRD management but also reduces the necessity of repeated antibiotic treatment, supporting prudent use of antimicrobials in livestock.