Efficacy of doxycycline in a goat model of Pasteurella pneumonia

The clinical efficacy of doxycycline (Doxycen, Cenavisa, Spain), a long-acting preparation, was evaluated for treatment of Pasteurella haemolytica infection in 6 goats. One goat was not infected and served as a control. The disease was induced by intratracheal inoculation of 10(7) to 10(9) cfu of P. haemolytica. Confirmation of respiratory disease was based on evidence of appropriate clinical signs. Before and after initiation of doxycycline treatment on day 10, each goat was examined daily. Three clinical responses to doxycycline treatment were noted. Mean rectal temperatures decreased from 40.1 degrees C to normal, while mean respiratory rate decreased from the pre-treatment value of 32 to 27/min after 4 days. Other clinical signs associated with pneumonia resolved within 3-5 days post treatment. In addition the minimum inhibitory concentration of DOTC for the P. haemolytica isolate was found to be < 0.5 microgram/ml. The present study indicates that DOTC may be a useful antimicrobial agent in the treatment of caprine pasteurellosis.