Objective: To use two diagnostic antigens belonging to the frequently associated in Theileria domain, Theileria equi (T. equi) protein 82 (Te 82) and T. equi 104 kDa microneme-rhoptry antigen precursor (Te 43), to diagnose T. equi infection in horses as compared with equi merozoite antigen-2 (EMA-2). Methods: In the current study, we applied a cocktail-ELISA containing two antigens (EMA-2 + Te 82) to diagnose T. equi infection either in experimentally infected horses or in field infection. Results: Our findings have revealed that a cocktail formula of EMA-2 + Te 82 provided a more practical and sensitive diagnostic candidate for diagnosing T. equi infection in horses as compared with Te 82 or Te 43 alone. Conclusions: The ELISA technique using a cocktail formula of EMA-2 + Te 82 offers a practical and sensitive diagnostic tool for diagnosing T. equi infection in horses and using of this promising cocktail formula will be applicable for epidemiological surveys and will help control the infection in horses.

Objective: To evaluate the combination therapy of pyronaridine tetraphosphate and diminazene aceturate against Babesia in vitro and in vivo. Methods: Bioinformatic analysis was performed using atom pair fingerprints. An in vitro combination test was performed against Babesia bovis and Theileria equi. Moreover, the in vivo chemotherapeutic efficacy of pyronaridine tetraphosphate in combination with diminazene aceturate was investigated against the growth of Babesia microti in mice using a fluorescence inhibitory assay. Results: Pyronaridine tetraphosphate and diminazene aceturate exhibited nearly similar molecular weights. The in vitro combination of pyronaridine tetraphosphate and diminazene aceturate was synergistic on Babesia bovis and additive on Theileria equi. In addition, 5 mg/kg pyronaridine tetraphosphate combined with 10 mg/kg diminazene aceturate inhibited Babesia microti growth significantly compared with those observed after treatment with 25 mg/kg diminazene aceturate alone from day 6 post treatment to day 12 post treatment. The combination therapy also normalized the hematological parameters of infected mice. Conclusions: An oral dose of pyronaridine tetraphosphate combined with a subcutaneous dose of diminazene aceturate inhibits Babesia in vitro and in mice, suggesting it might be a new paradigm for the treatment of babesiosis.