A Long-acting tetracycline for treatment of Pasteurella pneumonia in calves

Abstract

Fourteen Holstein steer calves were stressed by wetting alternately with hot and cold water 30, 28, 24 and 8 h before inoculation of 20 infective units of Pasteurella multocida by endotracheal tube. After 2 h all calves were dull, anorexic, had increased respiratory rate with coughing, and increased rectal temperature. Five calves were then injected with 2.27 mg/kg of a tetracycline T-50 (50mg oxytetracycline/ml) and 5 with a long-acting tetracycline T-200 (200 mg oxytetracycline/ml). Clinical symptoms persisted in the unmedicated calves and two died after 20 and 72h. Calves treated with T-50 recovered after 16h, while those treated with T-200 recovered slowly; there was no obvious improvement by 16h. However, after 2 days there was no difference between T-50 and T-200 treatments.