A high-quality genome sequence of the equine apicomplexan hemoparasite Theileria haneyi Eagle Pass isolate

Authors: Kappmeyer, Lowell; GRIMSLEY, MALISSA - Animal And Plant Health Inspection Service (APHIS); HICKS, JESSICA - Animal And Plant Health Inspection Service (APHIS); Bastos, Reginaldo

Submitted to: American Society for Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/21/2025
Publication Date: 12/12/2025
Citation: Kappmeyer, L.S., Grimsley, M.A., Hicks, J.A., Bastos, R.G. 2025. A high-quality genome sequence of the equine apicomplexan hemoparasite Theileria haneyi Eagle Pass isolate. American Society for Microbiology. 15(1). Article e00563-25. https://doi.org/10.1128/mra.00563-25.
DOI: https://doi.org/10.1128/mra.00563-25

Interpretive Summary: Theileria haneyi is a tick-borne apicomplexan hemoparasite that, alongside Theileria equi and Babesia caballi, causes equine piroplasmosis, an economically important disease of equids characterized by anemia, fever, and sudden death. Equine piroplasmosis is a reportable disease to the World Organisation for Animal Health (WOAH) and poses a major barrier to the global movement of equines. In this study, the complete genome of the T. haneyi Eagle Pass strain was sequenced using two different platforms. The resulting data produced a high-quality, fully assembled sequence of the four nuclear chromosomes of the parasite, as well as its mitochondrial and apicoplast genomes. This represents a substantial improvement over the previously available draft genome of T. haneyi. The availability of this high-quality genome sequence will support future research aimed at developing control strategies for T. haneyi and enable comparative studies with T. equi, potentially advancing efforts to control equine piroplasmosis.

Technical Abstract: The complete genome of the equine apicomplexan tickborne hemoparasite Theileria haneyi, Eagle Pass strain, was sequenced using both the Illumina Miseq and Nanopore technologies. The data generated a high-quality, fully assembled sequence for four nuclear chromosomes, as well as the mitochondrial and apicoplast genomes.