COMPARISON OF DANOFLOXACIN WITH BAQUILOPRIM SULPHADIMIDINE FOR THE TREATMENT OF EXPERIMENTALLY-INDUCED ESCHERICHIA-COLI DIARRHEA IN CALVES/

Thirty-eight, one- to two-week-old calves with experimentally induced Escherichia coli diarrhoea were randomly assigned to three treatment g roups. Two groups of 15 calves were treated intramuscularly once daily for three days with either danofloxacin mesylate at 1.25 mg/kg bodywe ight, or with baquiloprim/sulphadimidine as a positive control (10 mg of combined active ingredient/kg); eight calves were treated with 0.9 per cent sodium chloride solution as a negative control (1 ml/20 kg), Faecal consistency, demeanour, hydration status, appetite and bodyweig ht mere monitored before, during, and for four days after treatment by an investigator unaware of the animals' treatment. Before treatment, the clinical, biochemical, and faecal indices were similar among the g roups. By 24 hours after treatment began, the proportion of observatio ns of faeces recorded as of normal consistency was highest in the dano floxacin-treated group (26 of 60), compared with 16 of 60 in the baqui loprim/sulphadimidine treated groups and four of 32 in the control gro up. The proportion of calves with a normal demeanour was highest in th e danofloxacin-treated group at all the evaluations and these calves g ained significantly (P<0.05) more weight (1.6 [0.27] kg) than the calv es treated with baquiloprim/sulphadimidine (0.67 [0.36] kg), The calve s in the danofloxacin-treated group maintained relatively normal blood pH values, whereas the calves in the control group became progressive ly acidotic, By the end of treatment, the mean bicarbonate concentrati on was significantly (P<0.05) higher in the danofloxacin-treated calve s than in the control group. The pH of the calves in the baquiloprim/s ulphadimidine-treated group changed little during treatment, but by th ree days after the last treatment their mean pH had dropped to the lev el of the calves in the control group. The mean bicarbonate concentrat ion of the baquiloprim/sulphadimidine-treated calves, like that of the danofloxacin-treated calves, was significantly (P<0.05) higher than t hat of the calves in the control group.