The first study of the prevalence and genetic diversity of Theileria equi and Babesia caballi in horses in Russia.

Equine piroplasmosis (EP) is a global worldwide infection, which can lead to the death of animals. Despite the causative agents of EP being well studied, there are no data on the distribution and genetic characteristics of EP agents in any region of Russia. In this study, blood samples from 750 horses from Novosibirsk province, Irkutsk province, and Altai region of Russian Siberia were examined for the presence of EP agents. Theileria equi and Babesia caballi were detected in all examined regions, with mean prevalence rates of 60.4% and 7.2%, respectively. The identified pathogens were genetically characterized by the 18S rRNA gene. The determined T. equi sequences were highly conserved and belonged to genotypes A and E, with genotype E being found in 88.6% of genotyped samples. In contrast to T. equi, B. caballi sequences were genetically diverse. Seven sequence variants of B. caballi were identified, and only two of them matched known sequences from the GenBank database. The determined B. caballi sequences belonged to four distinct branches within genotype A. Mixed infections with several variants of B. caballi or with T. equi and B. caballi were common. The conducted phylogenetic analysis based on all available B. caballi sequences of the 18S rRNA gene (> 900 bp) from GenBank and from this study first demonstrated the presence of five monophyletic clusters within genotype A and three clusters within genotype B. Thus, the genetic study of B. caballi from Siberia has significantly expanded the data on the genetic diversity of this pathogen.

Synthesis and Clinical Examination of Novel Formulations of Ivermectin, Albendazole and Niclosamide for the Treatment of Equine Gastrointestinal Helminthoses.

Background: This study aimed to develop new complex preparations of ivermectin, niclosamide and albendazole based on solid-phase mechanochemical technology, and to evaluate their efficacy against equine nematodosis and cestodosis. Methods: Novel formulation of antiparasitic paste were prepared using joint mechano-chemical treatment of ivermectin (0.2 mg/kg bodyweight; BW), niclosamide (10 mg/kg BW) and albendazole (3, 5, 10 mg/kg BW) substances with polyvinylpyrrolidone and arabinogalactan. For the evaluation of activity of different doses of formulations against gastrointestinal tract helminths a total of 151 adult horses of the Novoaltai breed weighing 450-500 kg naturally infected with strongyles (>150 egg per gram of faeces, EPG), Parascaris spp. (>20 EPG) and Anoplocephala spp. (>10 EPG) were selected. Antiparasitic pastes were orally fed to the horses and faecal egg count reduction counts were compared prior to and 14 days after the treatment. Results: Pastes with mechanically modified ivermectin showed 91.4-100% efficacy against strongyles and Parascaris. Pastes with modified albendazole and niclosamide were also effective against Anoplocephala in all tested dosages i.e. 78.6-100%. In particular, treatment with two formulations containing i) 0.2 mg ivermectin, 10 mg albendazole, 10 mg niclosamide, and ii) 0.2 mg ivermectin, 3 mg albendazole showed 100% efficacy against strongyles, Parascaris and Anoplocephala. Conclusion: Solid-phase mechanochemical technology could be applied in equine anthelminthics production. It is suggested that future studies focus on plasma concentration-time profile of these highly effective pastes.

Efficacy of Novel Formulations of Ivermectin and Albendazole in Parasitic Infections of Sheep in the Altai Mountains of Russia.

BACKGROUND: Parasitic infections are widespread in sheep farms of the Russian Federation, including Siberia. The infection of sheep with helminths and parasitic arthropods with a range of 70% to 100% in different regions, contributes to a decrease in the productivity and quality of products, and even death of animals. This study aimed to formulate drugs with pronounced parasiticidal effects based on ivermectin and albendazole, widely used to treat animal entomoses and helminth infections. METHODS: New formulations in the form of solid dispersed compositions were prepared by mechanochemical modification of ivermectin and albendazole using arabinogalactan polysaccharide. The efficacy of preparations on gastrointestinal strongylosis and monieziosis, and melophagosis of sheep was determined by parasitological examination and analysis of feces and urine. RESULTS: The new formulations demonstrated increased solubility and parasiticidal activity due to the formation of inclusion complexes when interact with water. The maximum efficacy values (> 95% efficiency) against intestinal Strongylida and Moniezia expansa, and ectoparasitic Melophagus ovinus were seen in doses lower than the recommended doses of the starting drugs. CONCLUSION: The increased parasiticidal activity of innovative compositions can be explained by increased water solubility and bioavailability of the preparations, due to formation of inclusion complexes. The results of this study suggests the possibility of a significant reduction in the dosages of composed substances without losing their parasiticidal activity.

Innovative anthelmintic based on mechanochemical technology and their efficacy against parasitic infection of sheeps.

OBJECTIVE: Solubility and bioavailability are crucial for maximizing the activity of an antiparasitic drug. This study aimed to develop a combined preparation for antiparasitic medicines using ivermectin (Iver), fenbendazole (FBZ), and triclabendazole (TBZ), considering their solubility, bioavailability, and activity. MATERIALS AND METHODS: Innovative preparations in solid dispersions (SD) were obtained using the joint mechanical processing of drug substances with polyvinylpyrrolidone (PVP) in an LE-101 roller mill. The preparations' efficacy was studied in 140 sheep spontaneously infected with gastrointestinal Strongylata, Dicrococelium dendriticum, Moniezia expansa, and Melophagus ovinus. The preparations were given individually to the sheep in the form of an aqueous suspension orally. Their effectiveness was evaluated using intravital and postmortem parasitological examinations. RESULTS: The results confirmed the increase in solubility of substances by 13-29 times. The experiments have shown the high efficacy of SD composition of FBZ/Iver/PVP (1/1/9) containing FBZ (at 3.0 mg/kg b/w) and Iver (at 0.2 mg/kg b/w) when used against gastrointestinal Strongylates and M. expansa (95.8% and 100%, respectively), to a lesser extent against M. ovinus (38.5%). The SD composition of TBZ/Iver/PVP (1/1/9) of TBZ (at 3.0 mg/kg b/w) and Iver (at 0.2 mg/kg b/w) showed a high efficacy against gastrointestinal Strongylata and D. dendriticum (96.8% and 100%, respectively) and less activity against M. ovinus (61.6%). CONCLUSION: The high parasiticidal activity of SD based on FBZ, TBZ, and Iver in comparison with initial substances is explained by the formation of inclusion complexes of these substances with PVP when SD is dissolved in water and the synergistic effect of the active substances of the preparations. The resulting complexes have increased solubility in water and bioavailability. The use of such an SD suggests a significant reduction in the dosages of FBZ and TBZ without losing parasiticidal activity.