Largo de la Torre, AndreaFerré Pérez, IgnacioSánchez Sánchez, RobertoRegidor Cerrillo, JavierOrtega Mora, Luis Miguel2025-05-142025-05-142025-04-02Largo-de la Torre, A., Ferre, I., Sánchez-Sánchez, R., Regidor-Cerrillo, J., Ortega-Mora, L.M (2025) Characterization of a novel murine model of Toxoplasma gondii infection using oocysts of a recently obtained Type III isolate. Vet Res 56, 73. https://doi.org/10.1186/s13567-025-01507-x0928-424910.1186/s13567-025-01507-xhttps://hdl.handle.net/20.500.14352/120104Contributions: LMOM, JRC and IF conceived the study and participated in its design. RSS carried out the oocyst production and, together with ALT, participated in the inoculation of animals. ALT conducted the clinical examination of animals, performed necropsies and collected samples. JRC and ALT analyzed the data, carried out statistical analyses and interpreted the results. ALT and JRC wrote the manuscript with result interpretation and inputs from LMOM and I.F. All authors read and approved the final manuscript.Type II reference isolates of Toxoplasma gondii are widely used in animal toxoplasmosis models, but studies with Type III isolates remain scarce. In addition, these methods often rely on laboratory-adapted parasite stages that may not reflect natural infection. This study presents a new murine model based on an oral infection with oocysts from a recently obtained Type III isolate, TgShSp24, which exhibited remarkable morbidity and a distinct tissue distribution during chronic infection, differing from the recently obtained Type II isolate TgShSp1. This novel model aims to better mimic natural infection and provides a valuable tool for testing drugs and vaccines.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article1297-9716https://doi.org/10.1186/s13567-025-01507-xopen access636.09Toxoplasma gondiiMouse modelOocystType II and Type IIIFeld isolateVeterinaria3109 Ciencias Veterinarias