Evaluation of the chemotherapeutic efficacy of moxifloxacin in experimental colibacteriosis of chickens

The goal of the present study was to assess the chemotherapeutic effectiveness of moxifloxacin, at various doses, in experimental colibacillosis of chickens. Day-old Hisex Brown chickens were experimentally infected via intraperitoneal injection with Escherichia coli in suspension at a dose of 1.5 x 10^8 CFUs / 0.5 mL per chicken. For the sake of the experiment, we divided the chickens into 3 groups (n=90, in each group). The dose of moxifloxacin for Group I was determined 5 mg/kg body weight, Group II – 10 mg/kg body weight and Group III – 20 mg/kg body weight. In each group the chickens were challenged intraperitoneally once (ten chickens at a time), at 1h, 2h, 3h, 4h, 6h, 8h, 10h, 12h following the challenge and simultaneously with the challenge. The results of our research prove that the therapeutic effectiveness of moxifloxacin at a dose of 5 mg/kg body weight, in experimental colibacillosis, irrespective of the moment of administration of the drug in regard to the moment of the challenge, was insignificant. Moxifloxacin at the dose of 5 mg/kg body weight was just scarcely effective when it was administered to the chickens at 1h and 10h following the challenge and simultaneously with the challenge (total life span = 31 -39%). Otherwise, the specified dose of the drug proved ineffective. When the dose was increased to 10 mg/kg body weight the therapeutic effectiveness of the drug increased likewise. When moxifloxacin was administered to the chickens simultaneously with the challenge the total life span was 57%, thus the dose can be considered effective. Similar results were achieved when the drug was administered to the chickens at 6h, 8h and 10h following the challenge (the total life span was 44-53%). The drug at a dose of 20 mg/kg body weight allowed to achieve higher effectiveness. Moxifloxacin at such dose ensured the total life span from 33% (administration at 12h following the challenge) to 75% (administration simultaneous with the challenge).

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