Clothier, K. A., Leavens, T., Griffith, R. W., Wetzlich, S. E., Baynes, R. E., Riviere, J. E., Tell, L. A. Pharmacokinetics of tulathromycin after single and multiple subcutaneous injections in domestic goats (Capra aegagrus hircus). J. vet. Pharmacol. Therap.34, 448–454.

Tulathromycin, a novel triamilide in the macrolide class, is labeled for treatment of bacterial pneumonia in cattle and swine. This manuscript evaluates pharmacokinetics of tulathromycin in goats. In two different studies, six juvenile and ten market-age goats received a single injection of 2.5 mg/kg of tulathromycin subcutaneously; in a third study, 18 juvenile goats were treated with 2.5, 7.5, or 12.5 mg/kg tulathromycin weekly with three subcutaneous injections. Pharmacokinetic parameters estimated from the plasma concentrations from single injections were similar between the two groups of goats and to previously reported parameters in cattle and swine. Mean terminal half-lives were 59.1 ± 7.6 and 61.2 ± 8.7 h for juvenile and market-age goats, respectively. In the multi-dose study, pharmacokinetic parameters estimated from plasma concentrations demonstrated significant differences at < 0.05 among repeated injections but not among doses. Overall, pharmacokinetic parameters in goats are similar to those reported in cattle and swine, and tulathromycin may prove a useful drug for treating respiratory disease in goats.