ABSTRACT
Background: The production of bovine theileriosis vaccine involves in vitro cultivation of Theileria annulata schizont-infected cell lines. Fetal bovine serum (FBS) is commonly used in animal cell culture, including the Theileria cell line. However, we aimed to reduce the amount of serum needed for cell culture by modifying the Stoker culture medium with supplements such as excretion factor and serum substitutes. Methods: To evaluate the effectiveness of these modifications, techniques such as cell counting, cell viability assays, and genomic analysis were employed in the Parasitic Vaccines Production Department of Razi institute of Iran, from 2020 to 2022. Statistical analysis was used to compare the results of different experimental conditions. Results: The three experimental media were as effective as the commonly used 10% Stoker medium in supporting the growth and viability of cells. Conclusion: The significant reduction in the required amount of serum and the remarkable cell growth achieved by using defined serum replacements for the production of cell culture media is a significant step towards the preparation of a proper cell culture medium for the production of bovine Theileriosis vaccine.
ABSTRACT
The present study aimed at evaluating the presence of tick-borne apicomplexan parasites including Theileria ovis, Theileria lestoquardi, Theileria annulata, and Theileria orientalis in 92 cattle and 105 sheep from 6 different districts of Guilan and Mazandaran Provinces, in the southern littoral of Caspian Sea. Furthermore, ixodid ticks were collected from the same animals. Stained blood smears were microscopically evaluated for the presence of blood parasites, and a specific PCR was applied for the detection of Theileria species. Besides, ticks were subsequently examined by species-specific PCR. Microscopic examination of blood smears demonstrated no evidence of intraerythrocytic piroplasms. Species-specific diagnostic PCRs demonstrated that 52.17% of sheep blood samples were positive for T. ovis. In addition, 31.03% and 24.13% of cattle blood samples were positive for T. annulata and T. orientalis, respectively. Moreover, 3 species of the ixodid ticks, namely, Rhipicephalus annulatus (58.47%), Ixodes ricinus (29.82%), and Haemaphysalis inermis (11.69%), were identified in Guilan Province, while Hyalomma detritum (73.03%) and Rhipicephalus sanguineus (26.92%) were found in Mazandaran Province. Additionally, by obtaining the data with respect to tick-borne apicomplexan parasites in 122 infected ticks, 35.24%, 22.95%, and 2.45% of tick samples were positive for T. annulata, T. orientalis, and T. ovis, respectively. Species-specific PCR revealed that H. inermis and R. annulatus were positive for T. orientalis. In addition, T. annulata was found in R. annulatus, H. inermis, and H. detritum. Besides, T. ovis was the only species of Theileria found in R. sanguineus. In conclusion, the results revealed that T. annulata infection was prevalent among cattle and ovine theileriosis caused by T. ovis was the only Theileria species found in sheep in the studied areas of the southern littoral of Caspian Sea. R. annulatus, H. inermis, and H. detritum were the main vectors for T. annulata, followed by H. inermis and R. annulatus for T. orientalis, and R. sanguineus for T. ovis.
