Evaluation of the effectiveness of the use of a complex of antibacterial drugs for the treatment of bacterial hemorrhagic septicemia in fish

Abstract

The aim of the study was to develop therapeutic measures to combat bacterial hemorrhagic septicemia of fish using a complex of antibacterial drugs “Levofloxacin” and “Chlortetracycline”.Methods used: experiments were carried out in aquarium conditions on juvenile carp and hybrids «Siberian sturgeon×Kaluga» (hereinafter hybrid SO×K) infected with a mixed culture of pathogens: highly pathogenic strains of Aeromonas sp., strains of R.R. Acinetobacter and Citrobacter. In the experiment, 2 variants of the use of antibiotics for a course of 7 days were tested. Bacteriological seeding of fish parenchymal organ samples was carried out on nutrient and differential diagnostic media.Novelty: it consists in working out the scheme of application for fish of a complex of new antibiotics for aquaculture.Results: the results of the evaluation of the therapeutic effect of antibiotics “Levofloxacin” + “Chlortetracycline” in the treatment of bacterial hemorrhagic septicemia are presented. The cessation of fish death was noted the next day after the start of therapy. Positive results were obtained in carp — with a combination of levofloxacin at a dosage of 1000 mg/kg of ichthyomass and chlortetracycline — 100 mg/kg of ichthyomass, in a hybrid of SO×K — 500 mg/kg of ichthyomass of levofloxacin + 200 mg/kg of ichthyomass of chlortetracycline. Evaluation of their combinations with different dosages did not show 100% effect. The difficulties of therapy have been identified, which are associated with the spread of strains of microorganisms resistant to antibacterial drugs.Practical significance: the developed method of therapy is effective, reduces the damage from the disease and can be recommended when developing measures to combat bacterial hemorrhagic septicemia in fish in aquaculture.