Severe acute bronchopneumonia was induced in 18 conventional Friesian-Holstein calves by inoculating them intratracheally with Pasteurella haemolytica type A1. Six of the calves received no treatment and served as controls. Six of the calves were treated with sodium ceftiofur and six were treated with sodium ceftiofur and flumethasone. The mortality rate in the group of calves treated with sodium ceftiofur and flumethasone was significantly lower and their clinical and haematological parameters returned to normal significantly faster than in the control calves and the calves treated with sodium ceftiofur alone.