Prophylactic efficacy of drugs against equine piroplasmidosis in Gorny Altai

Abstract

The purpose of the research is to study the prophylactic efficacy of piroplasmicides and to elucidate the effect of prophylactic doses of Imidocarb Dipropionate on the pathogen viability.Materials and methods. Babezan 12% was intramuscularly injected to 150 horses based on the active substance of Imidocarb Dipropionate at 2.5 mg/kg of the body weight and Neosidin M was injected to 30 horses twice at a dose of 2.5 mL per 100 kg of the live weight with a 15-day interval. The control group of animals did not receive the drug. The clinical follow-up of the experimental and control animals’ condition was done for 72 days. Before the experiment and 14 days after the drugs, blood samples were examined by the nested PCR in the presence of genus-specific primers from the 18S rRNA gene sequence for the Babesia spp. / Theileria spp. DNA. Species identification and genotyping of the detected Piroplasma were performed by sequencing 18S rRNA gene fragments.Results and discussion. Among 12 examined horses, 8 animals (66.7%) had the Piroplasmida DNA found in the blood samples, of which 50.0% were identified as Theileria equi and 16.7% as Babesia caballi. A high T. equi DNA prevalence (over 50.0%) indicates an endemic course of equine theileriosis. Babesan 12% in early chemotherapy of the horses helped to prevent the incidence of theileriosis within 48 and 59 days. Double chemotherapy of the horses with Neosidin M with a 15-day interval prevented the morbidity for 52 days. Babesan 12% at the preventive dose had no effect on the viability of persistent T. equi stages.