Sub-acute injection toxicity of Florfenicol VS 30

This study is aimed at identifying organs and/or target organs systems that are most sensitive to the toxic effect of the drug under study, as well as determining the level of cumulation and reversibility of pathological changes in the animal body influenced by the pharmacological substance. During a 14-day sub-acute (intramuscular injection) experiment on outbred rats, it has been found that doses of 2.260 mg/kg (1/5 of LD50=1.1300 mg/kg) and 1130 mg/kg (1/10 of LD50=1.1300 mg/kg) were toxic and the dose of 565 mg/ kg was threshold (1/20 of LD50=1.1300 mg/kg). The investigated product Florfenicol VS 30 (developed by VETSFERA, Russia) in the tested doses caused a significant decrease in the body weight and significant changes in hematological and biochemical blood parameters. Integral indices in test groups were characterized by severe depression, decreased food activity, weakened skeletal muscle tone, and poor skin turgor. Gastrointestinal disorders were observed during all weight recording periods, while animals were injected with toxic doses. By day 14 of the experiment, the drug at a dose of 565 mg/kg (tolerable level) caused no changes in the behavior of experimental rats or their functional states. The disturbed hemopoiesis and significant hypoproteinemia revealed were reversible.