Dogs with superficial or deep pyoderma (n = 228) presented to first opinion veterinarians (n = 20) were treated orally with either ibafloxacin, at a dosage of 15 mg/kg, or marbofloxacin, at a dosage of 2 mg/kg, once daily for 3-16 weeks. On initial presentation, 35% of the cases were classified as having recurrent pyoderma and 40% as having deep pyoderma. Staphylococci (mainly Staphylococcus intermedius) were isolated from over 90% of the cases. The average treatment periods were 41 +/- 26 and 38 +/- 21 days in the ibafloxacin and marbofloxacin groups, respectively. One week after the cessation of treatment, 74 and 81% of dogs (P > 0.05) in the ibafloxacin and marbofloxacin groups, respectively, were classified as having responded to treatment. One month after the cessation of treatment, 70% of the dogs in each group were still classified as cured or improved, and 3 and 11% (P < 0.05) in the ibafloxacin and marbofloxacin groups, respectively, were classified as having relapsed. Despite having different pharmacokinetic profiles, ibafloxacin and marbofloxacin produced similar results when used under field conditions at the recommended dosages.